72813565 has 24 divisors (see below), whose sum is σ = 97665624. Its totient is φ = 52060800.

The previous prime is 72813547. The next prime is 72813619. The reversal of 72813565 is 56531827.

It can be written as a sum of positive squares in 4 ways, for example, as 1258884 + 71554681 = 1122^2 + 8459^2 .

It is not a de Polignac number, because 72813565 - 2⁷ = 72813437 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 35919 + ... + 37891.

It is an arithmetic number, because the mean of its divisors is an integer number (4069401).

Almost surely, 2^72813565 is an apocalyptic number.

It is an amenable number.

72813565 is a deficient number, since it is larger than the sum of its proper divisors (24852059).

72813565 is a wasteful number, since it uses less digits than its factorization.

72813565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2061 (or 2050 counting only the distinct ones).

The product of its digits is 50400, while the sum is 37.

The square root of 72813565 is about 8533.0864873151. The cubic root of 72813565 is about 417.5778286068.

The spelling of 72813565 in words is "seventy-two million, eight hundred thirteen thousand, five hundred sixty-five".