72991628 has 12 divisors (see below), whose sum is σ = 128711352. Its totient is φ = 36216960.

The previous prime is 72991619. The next prime is 72991649. The reversal of 72991628 is 82619927.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 69125 + ... + 70172.

It is an arithmetic number, because the mean of its divisors is an integer number (10725946).

Almost surely, 2^72991628 is an apocalyptic number.

It is an amenable number.

72991628 is a deficient number, since it is larger than the sum of its proper divisors (55719724).

72991628 is a wasteful number, since it uses less digits than its factorization.

72991628 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139432 (or 139430 counting only the distinct ones).

The product of its digits is 108864, while the sum is 44.

The square root of 72991628 is about 8543.5137970275. The cubic root of 72991628 is about 417.9179421197.

The spelling of 72991628 in words is "seventy-two million, nine hundred ninety-one thousand, six hundred twenty-eight".