51221742775920 has 60 divisors (see below), whose sum is σ = 172019686158216. Its totient is φ = 13659131406720.

The previous prime is 51221742775901. The next prime is 51221742775937. The reversal of 51221742775920 is 2957724712215.

51221742775920 is a `hidden beast` number, since 5 + 1 + 2 + 2 + 1 + 7 + 42 + 7 + 7 + 592 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (60).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 35570653986 + ... + 35570655425.

Almost surely, 2^{51221742775920} is an apocalyptic number.

It is an amenable number.

51221742775920 is an abundant number, since it is smaller than the sum of its proper divisors (120797943382296).

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

51221742775920 is a wasteful number, since it uses less digits than its factorization.

51221742775920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71141309430 (or 71141309421 counting only the distinct ones).

The product of its (nonzero) digits is 4939200, while the sum is 54.

The spelling of 51221742775920 in words is "fifty-one trillion, two hundred twenty-one billion, seven hundred forty-two million, seven hundred seventy-five thousand, nine hundred twenty".