2501665665 has 8 divisors (see below), whose sum is σ = 4002665088. Its totient is φ = 1334221680.

The previous prime is 2501665637. The next prime is 2501665669. The reversal of 2501665665 is 5665661052.

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

It is not a de Polignac number, because 2501665665 - 2⁶ = 2501665601 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2501665669) 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, 83388841 + ... + 83388870.

It is an arithmetic number, because the mean of its divisors is an integer number (500333136).

Almost surely, 2^2501665665 is an apocalyptic number.

It is an amenable number.

2501665665 is a deficient number, since it is larger than the sum of its proper divisors (1500999423).

2501665665 is a wasteful number, since it uses less digits than its factorization.

2501665665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166777719.

The product of its (nonzero) digits is 324000, while the sum is 42.

The square root of 2501665665 is about 50016.6538764840. The cubic root of 2501665665 is about 1357.5101620747.

The spelling of 2501665665 in words is "two billion, five hundred one million, six hundred sixty-five thousand, six hundred sixty-five".