721685872 has 10 divisors (see below), whose sum is σ = 1398266408. Its totient is φ = 360842928.

The previous prime is 721685857. The next prime is 721685879. The reversal of 721685872 is 278586127.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721685879) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 22552668 + ... + 22552699.

Almost surely, 2^721685872 is an apocalyptic number.

It is an amenable number.

721685872 is a deficient number, since it is larger than the sum of its proper divisors (676580536).

721685872 is a wasteful number, since it uses less digits than its factorization.

721685872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45105375 (or 45105369 counting only the distinct ones).

The product of its digits is 376320, while the sum is 46.

The square root of 721685872 is about 26864.2117323401. The cubic root of 721685872 is about 896.9799479905.

The spelling of 721685872 in words is "seven hundred twenty-one million, six hundred eighty-five thousand, eight hundred seventy-two".