51891488 has 24 divisors (see below), whose sum is σ = 111449520. Its totient is φ = 23586880.

The previous prime is 51891487. The next prime is 51891491. The reversal of 51891488 is 88419815.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is not an unprimeable number, because it can be changed into a prime (51891481) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 73358 + ... + 74061.

It is an arithmetic number, because the mean of its divisors is an integer number (4643730).

Almost surely, 2^51891488 is an apocalyptic number.

It is an amenable number.

51891488 is an abundant number, since it is smaller than the sum of its proper divisors (59558032).

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

51891488 is a wasteful number, since it uses less digits than its factorization.

51891488 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147440 (or 147432 counting only the distinct ones).

The product of its digits is 92160, while the sum is 44.

The square root of 51891488 is about 7203.5746681769. The cubic root of 51891488 is about 372.9913052285.

The spelling of 51891488 in words is "fifty-one million, eight hundred ninety-one thousand, four hundred eighty-eight".