72639220 has 24 divisors (see below), whose sum is σ = 152901000. Its totient is φ = 28987392.

The previous prime is 72639211. The next prime is 72639239. The reversal of 72639220 is 2293627.

It can be written as a sum of positive squares in 4 ways, for example, as 116964 + 72522256 = 342^2 + 8516^2 .

It is a congruent number.

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, 4936 + ... + 13024.

It is an arithmetic number, because the mean of its divisors is an integer number (6370875).

Almost surely, 2^72639220 is an apocalyptic number.

It is an amenable number.

72639220 is an abundant number, since it is smaller than the sum of its proper divisors (80261780).

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

72639220 is a wasteful number, since it uses less digits than its factorization.

72639220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8547 (or 8545 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 31.

The square root of 72639220 is about 8522.8645419249. The cubic root of 72639220 is about 417.2442790811.

The spelling of 72639220 in words is "seventy-two million, six hundred thirty-nine thousand, two hundred twenty".