51557225664 has 224 divisors, whose sum is σ = 160362188800. Its totient is φ = 14312567808.

The previous prime is 51557225659. The next prime is 51557225693. The reversal of 51557225664 is 46652275515.

It is a tau number, because it is divible by the number of its divisors (224).

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11498367 + ... + 11502849.

Almost surely, 2^51557225664 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 51557225664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (80181094400).

51557225664 is an abundant number, since it is smaller than the sum of its proper divisors (108804963136).

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

51557225664 is a wasteful number, since it uses less digits than its factorization.

51557225664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4747 (or 4737 counting only the distinct ones).

The product of its digits is 2520000, while the sum is 48.

The spelling of 51557225664 in words is "fifty-one billion, five hundred fifty-seven million, two hundred twenty-five thousand, six hundred sixty-four".