51464401920 has 704 divisors, whose sum is σ = 197376652800. Its totient is φ = 12669419520.

The previous prime is 51464401913. The next prime is 51464401999. The reversal of 51464401920 is 2910446415.

51464401920 is a `hidden beast` number, since 5 + 1 + 4 + 644 + 0 + 1 + 9 + 2 + 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 63 ways as a sum of consecutive naturals, for example, 143354701 + ... + 143355059.

Almost surely, 2^51464401920 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 51464401920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98688326400).

51464401920 is an abundant number, since it is smaller than the sum of its proper divisors (145912250880).

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

51464401920 is a wasteful number, since it uses less digits than its factorization.

51464401920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 471 (or 447 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The spelling of 51464401920 in words is "fifty-one billion, four hundred sixty-four million, four hundred one thousand, nine hundred twenty".