51317821221756 has 24 divisors (see below), whose sum is σ = 120801242879184. Its totient is φ = 16954560403200.

The previous prime is 51317821221701. The next prime is 51317821221803. The reversal of 51317821221756 is 65712212871315.

51317821221756 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×51317821221756² (a number of 28 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 51317821221699 and 51317821221708.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18922499095 + ... + 18922501806.

It is an arithmetic number, because the mean of its divisors is an integer number (5033385119966).

Almost surely, 2^{51317821221756} is an apocalyptic number.

It is an amenable number.

51317821221756 is an abundant number, since it is smaller than the sum of its proper divisors (69483421657428).

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

51317821221756 is a wasteful number, since it uses less digits than its factorization.

51317821221756 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37845001021 (or 37845001019 counting only the distinct ones).

The product of its digits is 1411200, while the sum is 51.

The spelling of 51317821221756 in words is "fifty-one trillion, three hundred seventeen billion, eight hundred twenty-one million, two hundred twenty-one thousand, seven hundred fifty-six".