721730585 has 16 divisors (see below), whose sum is σ = 892684800. Its totient is φ = 559820160.

The previous prime is 721730573. The next prime is 721730609. The reversal of 721730585 is 585037127.

It is a happy number.

It is not a de Polignac number, because 721730585 - 2⁸ = 721730329 is a prime.

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 15 ways as a sum of consecutive naturals, for example, 22616 + ... + 44214.

It is an arithmetic number, because the mean of its divisors is an integer number (55792800).

Almost surely, 2^721730585 is an apocalyptic number.

It is an amenable number.

721730585 is a deficient number, since it is larger than the sum of its proper divisors (170954215).

721730585 is a wasteful number, since it uses less digits than its factorization.

721730585 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21808.

The product of its (nonzero) digits is 58800, while the sum is 38.

The square root of 721730585 is about 26865.0439232844. The cubic root of 721730585 is about 896.9984721331.

The spelling of 721730585 in words is "seven hundred twenty-one million, seven hundred thirty thousand, five hundred eighty-five".