51980840 has 32 divisors (see below), whose sum is σ = 117165960. Its totient is φ = 20755200.

The previous prime is 51980839. The next prime is 51980843. The reversal of 51980840 is 4808915.

It can be written as a sum of positive squares in 4 ways, for example, as 43112356 + 8868484 = 6566^2 + 2978^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 51980840.

It is not an unprimeable number, because it can be changed into a prime (51980843) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36950 + ... + 38330.

Almost surely, 2^51980840 is an apocalyptic number.

It is an amenable number.

51980840 is an abundant number, since it is smaller than the sum of its proper divisors (65185120).

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

51980840 is a wasteful number, since it uses less digits than its factorization.

51980840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2333 (or 2329 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 35.

The square root of 51980840 is about 7209.7739215595. The cubic root of 51980840 is about 373.2052671567.

The spelling of 51980840 in words is "fifty-one million, nine hundred eighty thousand, eight hundred forty".