721718336 has 28 divisors (see below), whose sum is σ = 1433783772. Its totient is φ = 360450048.

The previous prime is 721718299. The next prime is 721718339. The reversal of 721718336 is 633817127.

It can be written as a sum of positive squares in 2 ways, for example, as 521665600 + 200052736 = 22840^2 + 14144^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 721718336.

It is not an unprimeable number, because it can be changed into a prime (721718339) 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, 55076 + ... + 66908.

Almost surely, 2^721718336 is an apocalyptic number.

It is an amenable number.

721718336 is a deficient number, since it is larger than the sum of its proper divisors (712065436).

721718336 is a wasteful number, since it uses less digits than its factorization.

721718336 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12798 (or 12788 counting only the distinct ones).

The product of its digits is 42336, while the sum is 38.

The square root of 721718336 is about 26864.8159494905. The cubic root of 721718336 is about 896.9933975727.

The spelling of 721718336 in words is "seven hundred twenty-one million, seven hundred eighteen thousand, three hundred thirty-six".