51100510561 has 4 divisors (see below), whose sum is σ = 51118399492. Its totient is φ = 51082621632.

The previous prime is 51100510553. The next prime is 51100510607. The reversal of 51100510561 is 16501500115.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16501500115 = 5 ⋅3300300023.

It can be written as a sum of positive squares in 2 ways, for example, as 35109390625 + 15991119936 = 187375^2 + 126456^2 .

It is a cyclic number.

It is not a de Polignac number, because 51100510561 - 2³ = 51100510553 is a prime.

It is a super-2 number, since 2×51100510561² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51100510661) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8940180 + ... + 8945893.

It is an arithmetic number, because the mean of its divisors is an integer number (12779599873).

Almost surely, 2^51100510561 is an apocalyptic number.

It is an amenable number.

51100510561 is a deficient number, since it is larger than the sum of its proper divisors (17888931).

51100510561 is a wasteful number, since it uses less digits than its factorization.

51100510561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17888930.

The product of its (nonzero) digits is 750, while the sum is 25.

The spelling of 51100510561 in words is "fifty-one billion, one hundred million, five hundred ten thousand, five hundred sixty-one".