720172985 has 16 divisors (see below), whose sum is σ = 989978112. Its totient is φ = 492676800.

The previous prime is 720172909. The next prime is 720173009. The reversal of 720172985 is 589271027.

It is a de Polignac number, because none of the positive numbers 2^k-720172985 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8786 + ... + 38955.

It is an arithmetic number, because the mean of its divisors is an integer number (61873632).

Almost surely, 2^720172985 is an apocalyptic number.

It is an amenable number.

720172985 is a deficient number, since it is larger than the sum of its proper divisors (269805127).

720172985 is a wasteful number, since it uses less digits than its factorization.

720172985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48184.

The product of its (nonzero) digits is 70560, while the sum is 41.

The square root of 720172985 is about 26836.0389215696. The cubic root of 720172985 is about 896.3527228045.

The spelling of 720172985 in words is "seven hundred twenty million, one hundred seventy-two thousand, nine hundred eighty-five".