721642532 has 12 divisors (see below), whose sum is σ = 1360018716. Its totient is φ = 333065760.

The previous prime is 721642529. The next prime is 721642567. The reversal of 721642532 is 235246127.

It can be written as a sum of positive squares in 2 ways, for example, as 491331556 + 230310976 = 22166^2 + 15176^2 .

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 6938819 + ... + 6938922.

It is an arithmetic number, because the mean of its divisors is an integer number (113334893).

Almost surely, 2^721642532 is an apocalyptic number.

It is an amenable number.

721642532 is a deficient number, since it is larger than the sum of its proper divisors (638376184).

721642532 is a wasteful number, since it uses less digits than its factorization.

721642532 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13877758 (or 13877756 counting only the distinct ones).

The product of its digits is 20160, while the sum is 32.

The square root of 721642532 is about 26863.4050708394. The cubic root of 721642532 is about 896.9619919375.

Adding to 721642532 its reverse (235246127), we get a palindrome (956888659).

The spelling of 721642532 in words is "seven hundred twenty-one million, six hundred forty-two thousand, five hundred thirty-two".