51521156606640 has 80 divisors (see below), whose sum is σ = 182532097698048. Its totient is φ = 11776264366848.

The previous prime is 51521156606629. The next prime is 51521156606641. The reversal of 51521156606640 is 4660665112515.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 51521156606640.

It is not an unprimeable number, because it can be changed into a prime (51521156606641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15333675882 + ... + 15333679241.

Almost surely, 2^{51521156606640} is an apocalyptic number.

It is an amenable number.

51521156606640 is an abundant number, since it is smaller than the sum of its proper divisors (131010941091408).

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

51521156606640 is a wasteful number, since it uses less digits than its factorization.

51521156606640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30667355146 (or 30667355140 counting only the distinct ones).

The product of its (nonzero) digits is 1296000, while the sum is 48.

The spelling of 51521156606640 in words is "fifty-one trillion, five hundred twenty-one billion, one hundred fifty-six million, six hundred six thousand, six hundred forty".