51530211723863 has 4 divisors (see below), whose sum is σ = 53307115576440. Its totient is φ = 49753307871288.

The previous prime is 51530211723829. The next prime is 51530211723869. The reversal of 51530211723863 is 36832711203515.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51530211723863 is a prime.

It is a super-2 number, since 2×51530211723863² (a number of 28 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 (51530211723869) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 888451926245 + ... + 888451926302.

It is an arithmetic number, because the mean of its divisors is an integer number (13326778894110).

Almost surely, 2^{51530211723863} is an apocalyptic number.

51530211723863 is a deficient number, since it is larger than the sum of its proper divisors (1776903852577).

51530211723863 is a wasteful number, since it uses less digits than its factorization.

51530211723863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1776903852576.

The product of its (nonzero) digits is 907200, while the sum is 47.

The spelling of 51530211723863 in words is "fifty-one trillion, five hundred thirty billion, two hundred eleven million, seven hundred twenty-three thousand, eight hundred sixty-three".