51355380861 has 32 divisors (see below), whose sum is σ = 77062285440. Its totient is φ = 33798240000.

The previous prime is 51355380827. The next prime is 51355380889. The reversal of 51355380861 is 16808355315.

51355380861 is a `hidden beast` number, since 5 + 1 + 35 + 538 + 0 + 86 + 1 = 666.

It is not a de Polignac number, because 51355380861 - 2²⁵ = 51321826429 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51355380821) 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, 732271 + ... + 799331.

It is an arithmetic number, because the mean of its divisors is an integer number (2408196420).

Almost surely, 2^51355380861 is an apocalyptic number.

It is an amenable number.

51355380861 is a deficient number, since it is larger than the sum of its proper divisors (25706904579).

51355380861 is a wasteful number, since it uses less digits than its factorization.

51355380861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67434 (or 67428 counting only the distinct ones).

The product of its (nonzero) digits is 432000, while the sum is 45.

The spelling of 51355380861 in words is "fifty-one billion, three hundred fifty-five million, three hundred eighty thousand, eight hundred sixty-one".