51665715 has 16 divisors (see below), whose sum is σ = 91850400. Its totient is φ = 27554976.

The previous prime is 51665711. The next prime is 51665723. The reversal of 51665715 is 51756615.

51665715 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 51665715 - 2² = 51665711 is a prime.

It is a super-2 number, since 2×51665715² = 5338692212922450, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 51665715.

It is not an unprimeable number, because it can be changed into a prime (51665711) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 191220 + ... + 191489.

It is an arithmetic number, because the mean of its divisors is an integer number (5740650).

Almost surely, 2^51665715 is an apocalyptic number.

51665715 is a deficient number, since it is larger than the sum of its proper divisors (40184685).

51665715 is a wasteful number, since it uses less digits than its factorization.

51665715 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 382723 (or 382717 counting only the distinct ones).

The product of its digits is 31500, while the sum is 36.

The square root of 51665715 is about 7187.8866852504. The cubic root of 51665715 is about 372.4495735232.

The spelling of 51665715 in words is "fifty-one million, six hundred sixty-five thousand, seven hundred fifteen".