51375520 has 72 divisors (see below), whose sum is σ = 141212484. Its totient is φ = 17611776.

The previous prime is 51375469. The next prime is 51375521. The reversal of 51375520 is 2557315.

It can be written as a sum of positive squares in 2 ways, for example, as 50183056 + 1192464 = 7084^2 + 1092^2 .

It is a Harshad number since it is a multiple of its sum of digits (28).

It is not an unprimeable number, because it can be changed into a prime (51375521) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4564 + ... + 11116.

Almost surely, 2^51375520 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 51375520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (70606242).

51375520 is an abundant number, since it is smaller than the sum of its proper divisors (89836964).

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

51375520 is a wasteful number, since it uses less digits than its factorization.

51375520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6582 (or 6567 counting only the distinct ones).

The product of its (nonzero) digits is 5250, while the sum is 28.

The square root of 51375520 is about 7167.6718674895. The cubic root of 51375520 is about 371.7509413172.

The spelling of 51375520 in words is "fifty-one million, three hundred seventy-five thousand, five hundred twenty".