51145920 has 336 divisors, whose sum is σ = 209214720. Its totient is φ = 11225088.

The previous prime is 51145903. The next prime is 51145933. The reversal of 51145920 is 2954115.

It is a tau number, because it is divible by the number of its divisors (336).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 866851 + ... + 866909.

Almost surely, 2^51145920 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 51145920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104607360).

51145920 is an abundant number, since it is smaller than the sum of its proper divisors (158068800).

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

51145920 is a wasteful number, since it uses less digits than its factorization.

51145920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132 (or 119 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 27.

The square root of 51145920 is about 7151.6375747097. The cubic root of 51145920 is about 371.1963225458.

The spelling of 51145920 in words is "fifty-one million, one hundred forty-five thousand, nine hundred twenty".