65665202561 has 16 divisors (see below), whose sum is σ = 78591569664. Its totient is φ = 53642913984.

The previous prime is 65665202557. The next prime is 65665202573. The reversal of 65665202561 is 16520256656.

It is not a de Polignac number, because 65665202561 - 2² = 65665202557 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (65665202501) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 691610 + ... + 780803.

It is an arithmetic number, because the mean of its divisors is an integer number (4911973104).

Almost surely, 2^65665202561 is an apocalyptic number.

It is an amenable number.

65665202561 is a deficient number, since it is larger than the sum of its proper divisors (12926367103).

65665202561 is a wasteful number, since it uses less digits than its factorization.

65665202561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1472720.

The product of its (nonzero) digits is 648000, while the sum is 44.

The spelling of 65665202561 in words is "sixty-five billion, six hundred sixty-five million, two hundred two thousand, five hundred sixty-one".