51591232 has 168 divisors, whose sum is σ = 139354560. Its totient is φ = 18385920.

The previous prime is 51591229. The next prime is 51591247. The reversal of 51591232 is 23219515.

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

It is a self number, because there is not a number n which added to its sum of digits gives 51591232.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1778994 + ... + 1779022.

Almost surely, 2^51591232 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 51591232, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (69677280).

51591232 is an abundant number, since it is smaller than the sum of its proper divisors (87763328).

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

51591232 is a wasteful number, since it uses less digits than its factorization.

51591232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97 (or 68 counting only the distinct ones).

The product of its digits is 2700, while the sum is 28.

The square root of 51591232 is about 7182.7036692321. The cubic root of 51591232 is about 372.2705089144.

The spelling of 51591232 in words is "fifty-one million, five hundred ninety-one thousand, two hundred thirty-two".