816515645 has 16 divisors (see below), whose sum is σ = 1069547328. Its totient is φ = 593466240.

The previous prime is 816515629. The next prime is 816515653. The reversal of 816515645 is 546515618.

It is not a de Polignac number, because 816515645 - 2⁴ = 816515629 is a prime.

It is a Duffinian number.

It is a congruent 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, 114062 + ... + 121008.

It is an arithmetic number, because the mean of its divisors is an integer number (66846708).

Almost surely, 2^816515645 is an apocalyptic number.

It is an amenable number.

816515645 is a deficient number, since it is larger than the sum of its proper divisors (253031683).

816515645 is a wasteful number, since it uses less digits than its factorization.

816515645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9100.

The product of its digits is 144000, while the sum is 41.

The square root of 816515645 is about 28574.7378815624. The cubic root of 816515645 is about 934.6625394325.

The spelling of 816515645 in words is "eight hundred sixteen million, five hundred fifteen thousand, six hundred forty-five".