51358812660 has 72 divisors (see below), whose sum is σ = 161160428520. Its totient is φ = 13223417088.

The previous prime is 51358812649. The next prime is 51358812691. The reversal of 51358812660 is 6621885315.

51358812660 is a `hidden beast` number, since 5 + 1 + 3 + 588 + 1 + 2 + 6 + 60 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 1224020196 + 50134792464 = 34986^2 + 223908^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4914207 + ... + 4924646.

It is an arithmetic number, because the mean of its divisors is an integer number (2238339285).

Almost surely, 2^51358812660 is an apocalyptic number.

It is an amenable number.

51358812660 is an abundant number, since it is smaller than the sum of its proper divisors (109801615860).

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

51358812660 is a wasteful number, since it uses less digits than its factorization.

51358812660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9838897 (or 9838892 counting only the distinct ones).

The product of its (nonzero) digits is 345600, while the sum is 45.

The spelling of 51358812660 in words is "fifty-one billion, three hundred fifty-eight million, eight hundred twelve thousand, six hundred sixty".