30,000

• 30029 = primorial prime
• 30030 = primorial[1]
• 30203 = safe prime
• 30240 = harmonic divisor number[2]
• 30323 = Sophie Germain prime and safe prime
• 30420 = pentagonal pyramidal number[3]
• 30537 = Riordan number
• 30694 = open meandric number
• 30941 = first base 13 repunit prime

• 31116 = octahedral number[4]
• 31337 = cousin prime, pronounced elite, an alternate way to spell 1337, an obfuscated alphabet made with numbers and punctuation, known and used in the gamer, hacker, and BBS cultures.
• 31395 = square pyramidal number
• 31397 = prime number followed by a record prime gap of 72, the first greater than 52[5]
• 31688 = the number of years approximately equal to 1 trillion seconds
• 31721 = start of a prime quadruplet[6]
• 31929 = Zeisel number[7]

• 32043 = smallest number whose square is pandigital.
• 32045 = can be expressed as a sum of two squares in more ways than any smaller number.[8]
• 32760 = harmonic divisor number[2]
• 32761 = 181², centered hexagonal number
• 32767 = 2¹⁵ − 1, largest positive value for a signed (two's complement) 16-bit integer on a computer.
• 32768 = 2¹⁵ = 8⁵, maximum absolute value of a negative value for a signed (two's complement) 16-bit integer on a computer.
• 32800 = pentagonal pyramidal number[3]
• 32993 = Leyland number[9]

• 33333 = repdigit
• 33461 = Pell number,[10] Markov number[11]
• 33511 = square pyramidal number
• 33781 = octahedral number[4]

• 34560 = 5 superfactorial[12]
• 34790 = number of non-isomorphic set-systems of weight 13.
• 34841 = start of a prime quadruplet[6]
• 34969 = favorite number of the Muppet character Count von Count[13]

• 35720 = square pyramidal number
• 35840 = number of ounces in a long ton (2,240 pounds)
• 35890 = tribonacci number[14]
• 35899 = alternating factorial[15]
• 35937 = 33³, chiliagonal number[16]
• 35964 = digit-reassembly number

• 36100 = sum of the cubes of the first 19 positive integers
• 36463 – number of parallelogram polyominoes with 14 cells[17]
• 36594 = octahedral number[4]

• 37378 = semi-meandric number[18]
• 37634 = third term of the Lucas–Lehmer sequence
• 37666 = Markov number[11]
• 37926 = pentagonal pyramidal number[3]

• 38024 = square pyramidal number
• 38209 = n such that n | (3ⁿ + 5)[19]
• 38416 = 14⁴
• 38807 = number of non-equivalent ways of expressing 10,000,000 as the sum of two prime numbers[20]
• 38962 = Kaprekar number[21]

• 39304 = 34³
• 39559 = octahedral number[4]
• 39648 = tetranacci number[22]

There are 958 prime numbers between 30000 and 40000.