72131931 has 16 divisors (see below), whose sum is σ = 107184000. Its totient is φ = 47943144.

The previous prime is 72131921. The next prime is 72131963. The reversal of 72131931 is 13913127.

It is not a de Polignac number, because 72131931 - 2¹⁹ = 71607643 is a prime.

It is a super-2 number, since 2×72131931² = 10406030939577522, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 72131895 and 72131904.

It is not an unprimeable number, because it can be changed into a prime (72131921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5520 + ... + 13218.

It is an arithmetic number, because the mean of its divisors is an integer number (6699000).

Almost surely, 2^72131931 is an apocalyptic number.

72131931 is a deficient number, since it is larger than the sum of its proper divisors (35052069).

72131931 is a wasteful number, since it uses less digits than its factorization.

72131931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8055 (or 8049 counting only the distinct ones).

The product of its digits is 1134, while the sum is 27.

The square root of 72131931 is about 8493.0519249561. The cubic root of 72131931 is about 416.2707091393.

The spelling of 72131931 in words is "seventy-two million, one hundred thirty-one thousand, nine hundred thirty-one".