51939520 has 56 divisors (see below), whose sum is σ = 129076704. Its totient is φ = 19869696.

The previous prime is 51939509. The next prime is 51939541. The reversal of 51939520 is 2593915.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3832 + ... + 10888.

Almost surely, 2^51939520 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 51939520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (64538352).

51939520 is an abundant number, since it is smaller than the sum of its proper divisors (77137184).

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

51939520 is a wasteful number, since it uses less digits than its factorization.

51939520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7097 (or 7087 counting only the distinct ones).

The product of its (nonzero) digits is 12150, while the sum is 34.

The square root of 51939520 is about 7206.9077973844. The cubic root of 51939520 is about 373.1063529574.

The spelling of 51939520 in words is "fifty-one million, nine hundred thirty-nine thousand, five hundred twenty".