641715985 has 16 divisors (see below), whose sum is σ = 804939264. Its totient is φ = 490197312.

The previous prime is 641715979. The next prime is 641716021. The reversal of 641715985 is 589517146.

It is a cyclic number.

It is not a de Polignac number, because 641715985 - 2⁵ = 641715953 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 65944 + ... + 75046.

It is an arithmetic number, because the mean of its divisors is an integer number (50308704).

Almost surely, 2^641715985 is an apocalyptic number.

It is an amenable number.

641715985 is a deficient number, since it is larger than the sum of its proper divisors (163223279).

641715985 is a wasteful number, since it uses less digits than its factorization.

641715985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9744.

The product of its digits is 302400, while the sum is 46.

The square root of 641715985 is about 25332.1137096769. The cubic root of 641715985 is about 862.5433923419.

The spelling of 641715985 in words is "six hundred forty-one million, seven hundred fifteen thousand, nine hundred eighty-five".