815566772097 has 48 divisors (see below), whose sum is σ = 1480864694400. Its totient is φ = 423671006880.

The previous prime is 815566772039. The next prime is 815566772113. The reversal of 815566772097 is 790277665518.

815566772097 is a `hidden beast` number, since 8 + 1 + 556 + 6 + 7 + 72 + 0 + 9 + 7 = 666.

It is not a de Polignac number, because 815566772097 - 2⁷ = 815566771969 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (815566774097) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4779222 + ... + 4946927.

It is an arithmetic number, because the mean of its divisors is an integer number (30851347800).

Almost surely, 2^815566772097 is an apocalyptic number.

It is an amenable number.

815566772097 is a deficient number, since it is larger than the sum of its proper divisors (665297922303).

815566772097 is a wasteful number, since it uses less digits than its factorization.

815566772097 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9726195 (or 9726170 counting only the distinct ones).

The product of its (nonzero) digits is 44452800, while the sum is 63.

The spelling of 815566772097 in words is "eight hundred fifteen billion, five hundred sixty-six million, seven hundred seventy-two thousand, ninety-seven".