721642055 has 8 divisors (see below), whose sum is σ = 868384800. Its totient is φ = 575704096.

The previous prime is 721642037. The next prime is 721642079. The reversal of 721642055 is 550246127.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 721642055 - 2²² = 717447751 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 199220 + ... + 202809.

It is an arithmetic number, because the mean of its divisors is an integer number (108548100).

Almost surely, 2^721642055 is an apocalyptic number.

721642055 is a deficient number, since it is larger than the sum of its proper divisors (146742745).

721642055 is a wasteful number, since it uses less digits than its factorization.

721642055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 402393.

The product of its (nonzero) digits is 16800, while the sum is 32.

The square root of 721642055 is about 26863.3961925889. The cubic root of 721642055 is about 896.9617943092.

The spelling of 721642055 in words is "seven hundred twenty-one million, six hundred forty-two thousand, fifty-five".