721663672 has 32 divisors (see below), whose sum is σ = 1380067920. Its totient is φ = 353687040.

The previous prime is 721663661. The next prime is 721663699. The reversal of 721663672 is 276366127.

721663672 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, 147408 + ... + 152224.

Almost surely, 2^721663672 is an apocalyptic number.

It is an amenable number.

721663672 is a deficient number, since it is larger than the sum of its proper divisors (658404248).

721663672 is a wasteful number, since it uses less digits than its factorization.

721663672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5191 (or 5187 counting only the distinct ones).

The product of its digits is 127008, while the sum is 40.

The square root of 721663672 is about 26863.7985400427. The cubic root of 721663672 is about 896.9707504713.

The spelling of 721663672 in words is "seven hundred twenty-one million, six hundred sixty-three thousand, six hundred seventy-two".