721684972 has 12 divisors (see below), whose sum is σ = 1263585960. Its totient is φ = 360660416.

The previous prime is 721684921. The next prime is 721684973. The reversal of 721684972 is 279486127.

It is not an unprimeable number, because it can be changed into a prime (721684973) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36397 + ... + 52612.

It is an arithmetic number, because the mean of its divisors is an integer number (105298830).

Almost surely, 2^721684972 is an apocalyptic number.

It is an amenable number.

721684972 is a deficient number, since it is larger than the sum of its proper divisors (541900988).

721684972 is a wasteful number, since it uses less digits than its factorization.

721684972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91040 (or 91038 counting only the distinct ones).

The product of its digits is 338688, while the sum is 46.

The square root of 721684972 is about 26864.1949814246. The cubic root of 721684972 is about 896.9795751217.

The spelling of 721684972 in words is "seven hundred twenty-one million, six hundred eighty-four thousand, nine hundred seventy-two".