51165665 has 8 divisors (see below), whose sum is σ = 65010600. Its totient is φ = 38524672.

The previous prime is 51165661. The next prime is 51165679. The reversal of 51165665 is 56656115.

51165665 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 18309841 + 32855824 = 4279^2 + 5732^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 51165665 - 2² = 51165661 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51165661) 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 7 ways as a sum of consecutive naturals, for example, 300890 + ... + 301059.

It is an arithmetic number, because the mean of its divisors is an integer number (8126325).

Almost surely, 2^51165665 is an apocalyptic number.

It is an amenable number.

51165665 is a deficient number, since it is larger than the sum of its proper divisors (13844935).

51165665 is a wasteful number, since it uses less digits than its factorization.

51165665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 601971.

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

The square root of 51165665 is about 7153.0178945673. The cubic root of 51165665 is about 371.2440834648.

The spelling of 51165665 in words is "fifty-one million, one hundred sixty-five thousand, six hundred sixty-five".