51061561617 has 32 divisors (see below), whose sum is σ = 75037003776. Its totient is φ = 30883662480.

The previous prime is 51061561613. The next prime is 51061561637. The reversal of 51061561617 is 71616516015.

It is not a de Polignac number, because 51061561617 - 2² = 51061561613 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51061561613) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1995768 + ... + 2021190.

It is an arithmetic number, because the mean of its divisors is an integer number (2344906368).

Almost surely, 2^51061561617 is an apocalyptic number.

It is an amenable number.

51061561617 is a deficient number, since it is larger than the sum of its proper divisors (23975442159).

51061561617 is a wasteful number, since it uses less digits than its factorization.

51061561617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25962 (or 25940 counting only the distinct ones).

The product of its (nonzero) digits is 37800, while the sum is 39.

The spelling of 51061561617 in words is "fifty-one billion, sixty-one million, five hundred sixty-one thousand, six hundred seventeen".