72724013 has 2 divisors, whose sum is σ = 72724014. Its totient is φ = 72724012.

The previous prime is 72724009. The next prime is 72724021. The reversal of 72724013 is 31042727.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 71944324 + 779689 = 8482^2 + 883^2 .

It is a cyclic number.

It is not a de Polignac number, because 72724013 - 2² = 72724009 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72724033) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36362006 + 36362007.

It is an arithmetic number, because the mean of its divisors is an integer number (36362007).

Almost surely, 2^72724013 is an apocalyptic number.

It is an amenable number.

72724013 is a deficient number, since it is larger than the sum of its proper divisors (1).

72724013 is an equidigital number, since it uses as much as digits as its factorization.

72724013 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2352, while the sum is 26.

The square root of 72724013 is about 8527.8375336307. The cubic root of 72724013 is about 417.4065680702.

The spelling of 72724013 in words is "seventy-two million, seven hundred twenty-four thousand, thirteen".