51897618432 has 416 divisors, whose sum is σ = 172412031360. Its totient is φ = 15288238080.

The previous prime is 51897618427. The next prime is 51897618467. The reversal of 51897618432 is 23481679815.

51897618432 is a `hidden beast` number, since 5 + 18 + 9 + 7 + 618 + 4 + 3 + 2 = 666.

It is a super-2 number, since 2×51897618432² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 45010368 + ... + 45011520.

Almost surely, 2^51897618432 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 51897618432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86206015680).

51897618432 is an abundant number, since it is smaller than the sum of its proper divisors (120514412928).

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

51897618432 is a wasteful number, since it uses less digits than its factorization.

51897618432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1234 (or 1206 counting only the distinct ones).

The product of its digits is 2903040, while the sum is 54.

The spelling of 51897618432 in words is "fifty-one billion, eight hundred ninety-seven million, six hundred eighteen thousand, four hundred thirty-two".