72157806 has 48 divisors (see below), whose sum is σ = 179154144. Its totient is φ = 20561472.

The previous prime is 72157769. The next prime is 72157817. The reversal of 72157806 is 60875127.

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, 81840 + ... + 82716.

It is an arithmetic number, because the mean of its divisors is an integer number (3732378).

Almost surely, 2^72157806 is an apocalyptic number.

72157806 is an abundant number, since it is smaller than the sum of its proper divisors (106996338).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

72157806 is a wasteful number, since it uses less digits than its factorization.

72157806 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1545 (or 1542 counting only the distinct ones).

The product of its (nonzero) digits is 23520, while the sum is 36.

The square root of 72157806 is about 8494.5750923751. The cubic root of 72157806 is about 416.3204777452.

The spelling of 72157806 in words is "seventy-two million, one hundred fifty-seven thousand, eight hundred six".