51509688 has 32 divisors (see below), whose sum is σ = 129212160. Its totient is φ = 17111520.

The previous prime is 51509687. The next prime is 51509699. The reversal of 51509688 is 88690515.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51509683) 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, 3873 + ... + 10863.

It is an arithmetic number, because the mean of its divisors is an integer number (4037880).

Almost surely, 2^51509688 is an apocalyptic number.

It is an amenable number.

51509688 is an abundant number, since it is smaller than the sum of its proper divisors (77702472).

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

51509688 is a wasteful number, since it uses less digits than its factorization.

51509688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7307 (or 7303 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 42.

The square root of 51509688 is about 7177.0250104065. The cubic root of 51509688 is about 372.0742712151.

The spelling of 51509688 in words is "fifty-one million, five hundred nine thousand, six hundred eighty-eight".