51261599985 has 16 divisors (see below), whose sum is σ = 82443531264. Its totient is φ = 27197862912.

The previous prime is 51261599903. The next prime is 51261600041. The reversal of 51261599985 is 58999516215.

It is not a de Polignac number, because 51261599985 - 2¹⁰ = 51261598961 is a prime.

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, 8850577 + ... + 8856366.

It is an arithmetic number, because the mean of its divisors is an integer number (5152720704).

Almost surely, 2^51261599985 is an apocalyptic number.

It is an amenable number.

51261599985 is a deficient number, since it is larger than the sum of its proper divisors (31181931279).

51261599985 is a wasteful number, since it uses less digits than its factorization.

51261599985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17707144.

The product of its digits is 8748000, while the sum is 60.

The spelling of 51261599985 in words is "fifty-one billion, two hundred sixty-one million, five hundred ninety-nine thousand, nine hundred eighty-five".