51139606560 has 576 divisors, whose sum is σ = 198423146880. Its totient is φ = 11038906368.

The previous prime is 51139606549. The next prime is 51139606597. The reversal of 51139606560 is 6560693115.

It is a super-2 number, since 2×51139606560² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 161323522 + ... + 161323838.

It is an arithmetic number, because the mean of its divisors is an integer number (344484630).

Almost surely, 2^51139606560 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51139606560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (99211573440).

51139606560 is an abundant number, since it is smaller than the sum of its proper divisors (147283540320).

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

51139606560 is a wasteful number, since it uses less digits than its factorization.

51139606560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 406 (or 353 counting only the distinct ones).

The product of its (nonzero) digits is 145800, while the sum is 42.

The spelling of 51139606560 in words is "fifty-one billion, one hundred thirty-nine million, six hundred six thousand, five hundred sixty".