816495985 has 16 divisors (see below), whose sum is σ = 1017619200. Its totient is φ = 628452736.

The previous prime is 816495943. The next prime is 816496007. The reversal of 816495985 is 589594618.

It is a cyclic number.

It is not a de Polignac number, because 816495985 - 2²⁷ = 682278257 is a prime.

It is a super-2 number, since 2×816495985² = 1333331387042240450, which contains 22 as substring.

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, 15580 + ... + 43309.

It is an arithmetic number, because the mean of its divisors is an integer number (63601200).

Almost surely, 2^816495985 is an apocalyptic number.

It is an amenable number.

816495985 is a deficient number, since it is larger than the sum of its proper divisors (201123215).

816495985 is a wasteful number, since it uses less digits than its factorization.

816495985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59000.

The product of its digits is 3110400, while the sum is 55.

The square root of 816495985 is about 28574.3938693369. The cubic root of 816495985 is about 934.6550377950.

The spelling of 816495985 in words is "eight hundred sixteen million, four hundred ninety-five thousand, nine hundred eighty-five".