721938872 has 8 divisors (see below), whose sum is σ = 1353635400. Its totient is φ = 360969432.

The previous prime is 721938871. The next prime is 721938883. The reversal of 721938872 is 278839127.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721938871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45121172 + ... + 45121187.

It is an arithmetic number, because the mean of its divisors is an integer number (169204425).

Almost surely, 2^721938872 is an apocalyptic number.

It is an amenable number.

721938872 is a deficient number, since it is larger than the sum of its proper divisors (631696528).

721938872 is a wasteful number, since it uses less digits than its factorization.

721938872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90242365 (or 90242361 counting only the distinct ones).

The product of its digits is 338688, while the sum is 47.

The square root of 721938872 is about 26868.9201867139. The cubic root of 721938872 is about 897.0847532444.

The spelling of 721938872 in words is "seven hundred twenty-one million, nine hundred thirty-eight thousand, eight hundred seventy-two".