51191072768 has 192 divisors, whose sum is σ = 120313589760. Its totient is φ = 21532262400.

The previous prime is 51191072729. The next prime is 51191072819. The reversal of 51191072768 is 86727019115.

It is a super-2 number, since 2×51191072768² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16060871 + ... + 16064057.

It is an arithmetic number, because the mean of its divisors is an integer number (626633280).

Almost surely, 2^51191072768 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 51191072768, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (60156794880).

51191072768 is an abundant number, since it is smaller than the sum of its proper divisors (69122516992).

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

51191072768 is a wasteful number, since it uses less digits than its factorization.

51191072768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3274 (or 3254 counting only the distinct ones).

The product of its (nonzero) digits is 211680, while the sum is 47.

The spelling of 51191072768 in words is "fifty-one billion, one hundred ninety-one million, seventy-two thousand, seven hundred sixty-eight".