72931393 has 4 divisors (see below), whose sum is σ = 73653588. Its totient is φ = 72209200.

The previous prime is 72931387. The next prime is 72931399. The reversal of 72931393 is 39313927.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (72931387) and next prime (72931399).

It can be written as a sum of positive squares in 2 ways, for example, as 60093504 + 12837889 = 7752^2 + 3583^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72931393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72931399) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 360946 + ... + 361147.

It is an arithmetic number, because the mean of its divisors is an integer number (18413397).

Almost surely, 2^72931393 is an apocalyptic number.

It is an amenable number.

72931393 is a deficient number, since it is larger than the sum of its proper divisors (722195).

72931393 is a wasteful number, since it uses less digits than its factorization.

72931393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 722194.

The product of its digits is 30618, while the sum is 37.

The square root of 72931393 is about 8539.9878805535. The cubic root of 72931393 is about 417.8029507811.

The spelling of 72931393 in words is "seventy-two million, nine hundred thirty-one thousand, three hundred ninety-three".