721620564 has 24 divisors (see below), whose sum is σ = 1924321728. Its totient is φ = 206177280.

The previous prime is 721620547. The next prime is 721620593. The reversal of 721620564 is 465026127.

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, 4295277 + ... + 4295444.

It is an arithmetic number, because the mean of its divisors is an integer number (80180072).

Almost surely, 2^721620564 is an apocalyptic number.

It is an amenable number.

721620564 is an abundant number, since it is smaller than the sum of its proper divisors (1202701164).

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

721620564 is a wasteful number, since it uses less digits than its factorization.

721620564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8590735 (or 8590733 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 33.

The square root of 721620564 is about 26862.9961843425. The cubic root of 721620564 is about 896.9528901731.

The spelling of 721620564 in words is "seven hundred twenty-one million, six hundred twenty thousand, five hundred sixty-four".