51720621854376 has 16 divisors (see below), whose sum is σ = 129301554636000. Its totient is φ = 17240207284784.

The previous prime is 51720621854359. The next prime is 51720621854389. The reversal of 51720621854376 is 67345812602715.

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, 1077512955276 + ... + 1077512955323.

It is an arithmetic number, because the mean of its divisors is an integer number (8081347164750).

Almost surely, 2^{51720621854376} is an apocalyptic number.

It is an amenable number.

51720621854376 is an abundant number, since it is smaller than the sum of its proper divisors (77580932781624).

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

51720621854376 is a wasteful number, since it uses less digits than its factorization.

51720621854376 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2155025910608 (or 2155025910604 counting only the distinct ones).

The product of its (nonzero) digits is 16934400, while the sum is 57.

The spelling of 51720621854376 in words is "fifty-one trillion, seven hundred twenty billion, six hundred twenty-one million, eight hundred fifty-four thousand, three hundred seventy-six".