72557220 has 24 divisors (see below), whose sum is σ = 203160384. Its totient is φ = 19348576.

The previous prime is 72557213. The next prime is 72557231. The reversal of 72557220 is 2275527.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 604584 + ... + 604703.

It is an arithmetic number, because the mean of its divisors is an integer number (8465016).

Almost surely, 2^72557220 is an apocalyptic number.

It is an amenable number.

72557220 is an abundant number, since it is smaller than the sum of its proper divisors (130603164).

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

72557220 is a wasteful number, since it uses less digits than its factorization.

72557220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1209299 (or 1209297 counting only the distinct ones).

The product of its (nonzero) digits is 9800, while the sum is 30.

The square root of 72557220 is about 8518.0525943434. The cubic root of 72557220 is about 417.0872155677.

The spelling of 72557220 in words is "seventy-two million, five hundred fifty-seven thousand, two hundred twenty".