72307931 has 2 divisors, whose sum is σ = 72307932. Its totient is φ = 72307930.

The previous prime is 72307889. The next prime is 72308003. The reversal of 72307931 is 13970327.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 72307931 - 2²² = 68113627 is a prime.

It is a super-2 number, since 2×72307931² = 10456873771001522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (72367931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36153965 + 36153966.

It is an arithmetic number, because the mean of its divisors is an integer number (36153966).

Almost surely, 2^72307931 is an apocalyptic number.

72307931 is a deficient number, since it is larger than the sum of its proper divisors (1).

72307931 is an equidigital number, since it uses as much as digits as its factorization.

72307931 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7938, while the sum is 32.

The square root of 72307931 is about 8503.4070230702. The cubic root of 72307931 is about 416.6089973163.

The spelling of 72307931 in words is "seventy-two million, three hundred seven thousand, nine hundred thirty-one".