721455564 has 12 divisors (see below), whose sum is σ = 1683396344. Its totient is φ = 240485184.

The previous prime is 721455521. The next prime is 721455577. The reversal of 721455564 is 465554127.

It is a tau number, because it is divible by the number of its divisors (12).

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, 30060637 + ... + 30060660.

Almost surely, 2^721455564 is an apocalyptic number.

It is an amenable number.

721455564 is an abundant number, since it is smaller than the sum of its proper divisors (961940780).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

721455564 is a wasteful number, since it uses less digits than its factorization.

721455564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60121304 (or 60121302 counting only the distinct ones).

The product of its digits is 168000, while the sum is 39.

The square root of 721455564 is about 26859.9248695896. The cubic root of 721455564 is about 896.8845215984.

The spelling of 721455564 in words is "seven hundred twenty-one million, four hundred fifty-five thousand, five hundred sixty-four".