51156665 has 16 divisors (see below), whose sum is σ = 72422400. Its totient is φ = 33946560.

The previous prime is 51156661. The next prime is 51156671. The reversal of 51156665 is 56665115.

51156665 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 51156665 - 2² = 51156661 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (51156661) 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, 22490 + ... + 24659.

It is an arithmetic number, because the mean of its divisors is an integer number (4526400).

Almost surely, 2^51156665 is an apocalyptic number.

It is an amenable number.

51156665 is a deficient number, since it is larger than the sum of its proper divisors (21265735).

51156665 is a wasteful number, since it uses less digits than its factorization.

51156665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47192.

The product of its digits is 27000, while the sum is 35.

The square root of 51156665 is about 7152.3887618054. The cubic root of 51156665 is about 371.2223150082. Note that the first 3 decimals are identical.

The spelling of 51156665 in words is "fifty-one million, one hundred fifty-six thousand, six hundred sixty-five".