51638928 has 120 divisors (see below), whose sum is σ = 155552544. Its totient is φ = 14699520.

The previous prime is 51638927. The next prime is 51638929. The reversal of 51638928 is 82983615.

It is an interprime number because it is at equal distance from previous prime (51638927) and next prime (51638929).

It is a self number, because there is not a number n which added to its sum of digits gives 51638928.

It is not an unprimeable number, because it can be changed into a prime (51638927) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 98475 + ... + 98997.

Almost surely, 2^51638928 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 51638928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (77776272).

51638928 is an abundant number, since it is smaller than the sum of its proper divisors (103913616).

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

51638928 is a wasteful number, since it uses less digits than its factorization.

51638928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 573 (or 556 counting only the distinct ones).

The product of its digits is 103680, while the sum is 42.

The square root of 51638928 is about 7186.0231004360. The cubic root of 51638928 is about 372.3851947151.

The spelling of 51638928 in words is "fifty-one million, six hundred thirty-eight thousand, nine hundred twenty-eight".