51688165 has 4 divisors (see below), whose sum is σ = 62025804. Its totient is φ = 41350528.

The previous prime is 51688157. The next prime is 51688187. The reversal of 51688165 is 56188615.

51688165 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 30316036 + 21372129 = 5506^2 + 4623^2 .

It is a cyclic number.

It is not a de Polignac number, because 51688165 - 2³ = 51688157 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5168812 + ... + 5168821.

It is an arithmetic number, because the mean of its divisors is an integer number (15506451).

Almost surely, 2^51688165 is an apocalyptic number.

It is an amenable number.

51688165 is a deficient number, since it is larger than the sum of its proper divisors (10337639).

51688165 is a wasteful number, since it uses less digits than its factorization.

51688165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10337638.

The product of its digits is 57600, while the sum is 40.

The square root of 51688165 is about 7189.4481707569. The cubic root of 51688165 is about 372.5035118207.

The spelling of 51688165 in words is "fifty-one million, six hundred eighty-eight thousand, one hundred sixty-five".