51406431664 has 20 divisors (see below), whose sum is σ = 113828527504. Its totient is φ = 22031327808.

The previous prime is 51406431647. The next prime is 51406431689. The reversal of 51406431664 is 46613460415.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 229492887 + ... + 229493110.

Almost surely, 2^51406431664 is an apocalyptic number.

It is an amenable number.

51406431664 is an abundant number, since it is smaller than the sum of its proper divisors (62422095840).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51406431664 is a wasteful number, since it uses less digits than its factorization.

51406431664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 458986012 (or 458986006 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 40.

The spelling of 51406431664 in words is "fifty-one billion, four hundred six million, four hundred thirty-one thousand, six hundred sixty-four".