51187864 has 32 divisors (see below), whose sum is σ = 118127520. Its totient is φ = 20249856.

The previous prime is 51187861. The next prime is 51187937. The reversal of 51187864 is 46878115.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51187861) 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, 34429 + ... + 35884.

It is an arithmetic number, because the mean of its divisors is an integer number (3691485).

Almost surely, 2^51187864 is an apocalyptic number.

It is an amenable number.

51187864 is an abundant number, since it is smaller than the sum of its proper divisors (66939656).

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

51187864 is a wasteful number, since it uses less digits than its factorization.

51187864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70339 (or 70335 counting only the distinct ones).

The product of its digits is 53760, while the sum is 40.

The square root of 51187864 is about 7154.5694489606. The cubic root of 51187864 is about 371.2977656612.

The spelling of 51187864 in words is "fifty-one million, one hundred eighty-seven thousand, eight hundred sixty-four".