51389955620 has 24 divisors (see below), whose sum is σ = 108287243064. Its totient is φ = 20485822976.

The previous prime is 51389955601. The next prime is 51389955637. The reversal of 51389955620 is 2655998315.

It can be written as a sum of positive squares in 4 ways, for example, as 10019209216 + 41370746404 = 100096^2 + 203398^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4378949 + ... + 4390668.

It is an arithmetic number, because the mean of its divisors is an integer number (4511968461).

Almost surely, 2^51389955620 is an apocalyptic number.

It is an amenable number.

51389955620 is an abundant number, since it is smaller than the sum of its proper divisors (56897287444).

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

51389955620 is a wasteful number, since it uses less digits than its factorization.

51389955620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8769919 (or 8769917 counting only the distinct ones).

The product of its (nonzero) digits is 2916000, while the sum is 53.

The spelling of 51389955620 in words is "fifty-one billion, three hundred eighty-nine million, nine hundred fifty-five thousand, six hundred twenty".