51806638237431 has 32 divisors (see below), whose sum is σ = 86910218841600. Its totient is φ = 26665635300480.

The previous prime is 51806638237421. The next prime is 51806638237433. The reversal of 51806638237431 is 13473283660815.

It is not a de Polignac number, because 51806638237431 - 2⁹ = 51806638236919 is a prime.

It is a super-2 number, since 2×51806638237431² (a number of 28 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51806638237433) 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, 1028741616 + ... + 1028791973.

It is an arithmetic number, because the mean of its divisors is an integer number (2715944338800).

Almost surely, 2^{51806638237431} is an apocalyptic number.

51806638237431 is a deficient number, since it is larger than the sum of its proper divisors (35103580604169).

51806638237431 is a wasteful number, since it uses less digits than its factorization.

51806638237431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2057533719.

The product of its (nonzero) digits is 17418240, while the sum is 57.

The spelling of 51806638237431 in words is "fifty-one trillion, eight hundred six billion, six hundred thirty-eight million, two hundred thirty-seven thousand, four hundred thirty-one".