72356657 has 4 divisors (see below), whose sum is σ = 72614436. Its totient is φ = 72098880.

The previous prime is 72356639. The next prime is 72356701. The reversal of 72356657 is 75665327.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 75665327 = 31 ⋅2440817.

It can be written as a sum of positive squares in 2 ways, for example, as 60357361 + 11999296 = 7769^2 + 3464^2 .

It is a cyclic number.

It is not a de Polignac number, because 72356657 - 2⁶ = 72356593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72356357) 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, 128468 + ... + 129029.

It is an arithmetic number, because the mean of its divisors is an integer number (18153609).

Almost surely, 2^72356657 is an apocalyptic number.

It is an amenable number.

72356657 is a deficient number, since it is larger than the sum of its proper divisors (257779).

72356657 is a wasteful number, since it uses less digits than its factorization.

72356657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 257778.

The product of its digits is 264600, while the sum is 41.

The square root of 72356657 is about 8506.2716274523. The cubic root of 72356657 is about 416.7025561264.

The spelling of 72356657 in words is "seventy-two million, three hundred fifty-six thousand, six hundred fifty-seven".