51170975856 has 640 divisors, whose sum is σ = 200033863680. Its totient is φ = 12093235200.

The previous prime is 51170975831. The next prime is 51170975857. The reversal of 51170975856 is 65857907115.

It is a happy number.

51170975856 is a `hidden beast` number, since 51 + 1 + 7 + 0 + 9 + 7 + 585 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51170975857) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 31566726 + ... + 31568346.

It is an arithmetic number, because the mean of its divisors is an integer number (312552912).

Almost surely, 2^51170975856 is an apocalyptic number.

51170975856 is a gapful number since it is divisible by the number (56) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51170975856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (100016931840).

51170975856 is an abundant number, since it is smaller than the sum of its proper divisors (148862887824).

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

51170975856 is a wasteful number, since it uses less digits than its factorization.

51170975856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1742 (or 1730 counting only the distinct ones).

The product of its (nonzero) digits is 2646000, while the sum is 54.

The spelling of 51170975856 in words is "fifty-one billion, one hundred seventy million, nine hundred seventy-five thousand, eight hundred fifty-six".