51505756992 has 168 divisors, whose sum is σ = 154895816192. Its totient is φ = 16342041600.

The previous prime is 51505756963. The next prime is 51505756993. The reversal of 51505756992 is 29965750515.

51505756992 is a `hidden beast` number, since 5 + 1 + 5 + 0 + 575 + 69 + 9 + 2 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51505756993) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1065573 + ... + 1112859.

Almost surely, 2^51505756992 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 51505756992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (77447908096).

51505756992 is an abundant number, since it is smaller than the sum of its proper divisors (103390059200).

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

51505756992 is a wasteful number, since it uses less digits than its factorization.

51505756992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47397 (or 47384 counting only the distinct ones).

The product of its (nonzero) digits is 4252500, while the sum is 54.

The spelling of 51505756992 in words is "fifty-one billion, five hundred five million, seven hundred fifty-six thousand, nine hundred ninety-two".