721857542884 has 9 divisors (see below), whose sum is σ = 1263253673731. Its totient is φ = 360927921820.

The previous prime is 721857542849. The next prime is 721857542927. The reversal of 721857542884 is 488245758127.

The square root of 721857542884 is 849622.

It is a perfect power (a square), and thus also a powerful number.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 1486839 + ... + 1911649.

Almost surely, 2^721857542884 is an apocalyptic number.

721857542884 is the 849622-nd square number.

It is an amenable number.

721857542884 is a deficient number, since it is larger than the sum of its proper divisors (541396130847).

721857542884 is an frugal number, since it uses more digits than its factorization.

721857542884 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 849626 (or 424813 counting only the distinct ones).

The product of its digits is 40140800, while the sum is 61.

The spelling of 721857542884 in words is "seven hundred twenty-one billion, eight hundred fifty-seven million, five hundred forty-two thousand, eight hundred eighty-four".