51787856813 has 12 divisors (see below), whose sum is σ = 65719655712. Its totient is φ = 40354173720.

The previous prime is 51787856773. The next prime is 51787856821. The reversal of 51787856813 is 31865878715.

It is not a de Polignac number, because 51787856813 - 2²⁸ = 51519421357 is a prime.

It is a super-2 number, since 2×51787856813² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51787853813) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 48040145 + ... + 48041222.

It is an arithmetic number, because the mean of its divisors is an integer number (5476637976).

Almost surely, 2^51787856813 is an apocalyptic number.

It is an amenable number.

51787856813 is a deficient number, since it is larger than the sum of its proper divisors (13931798899).

51787856813 is a wasteful number, since it uses less digits than its factorization.

51787856813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96081392 (or 96081385 counting only the distinct ones).

The product of its digits is 11289600, while the sum is 59.

The spelling of 51787856813 in words is "fifty-one billion, seven hundred eighty-seven million, eight hundred fifty-six thousand, eight hundred thirteen".