51615291663 has 30 divisors (see below), whose sum is σ = 83491687224. Its totient is φ = 31763247984.

The previous prime is 51615291649. The next prime is 51615291667. The reversal of 51615291663 is 36619251615.

51615291663 is a `hidden beast` number, since 5 + 1 + 61 + 529 + 1 + 6 + 63 = 666.

It is not a de Polignac number, because 51615291663 - 2²⁵ = 51581737231 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51615291667) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 1871595 + ... + 1898972.

Almost surely, 2^51615291663 is an apocalyptic number.

51615291663 is a deficient number, since it is larger than the sum of its proper divisors (31876395561).

51615291663 is a wasteful number, since it uses less digits than its factorization.

51615291663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3770605 (or 3770583 counting only the distinct ones).

The product of its digits is 291600, while the sum is 45.

The spelling of 51615291663 in words is "fifty-one billion, six hundred fifteen million, two hundred ninety-one thousand, six hundred sixty-three".