51005641680 has 960 divisors, whose sum is σ = 213394341888. Its totient is φ = 11078000640.

The previous prime is 51005641679. The next prime is 51005641691. The reversal of 51005641680 is 8614650015.

51005641680 is a `hidden beast` number, since 5 + 1 + 0 + 0 + 5 + 641 + 6 + 8 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 451377304 + ... + 451377416.

Almost surely, 2^51005641680 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 51005641680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106697170944).

51005641680 is an abundant number, since it is smaller than the sum of its proper divisors (162388700208).

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

51005641680 is a wasteful number, since it uses less digits than its factorization.

51005641680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 286 (or 268 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 36.

The spelling of 51005641680 in words is "fifty-one billion, five million, six hundred forty-one thousand, six hundred eighty".