65610665 has 4 divisors (see below), whose sum is σ = 78732804. Its totient is φ = 52488528.

The previous prime is 65610631. The next prime is 65610683. The reversal of 65610665 is 56601656.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 51652969 + 13957696 = 7187^2 + 3736^2 .

It is a cyclic number.

It is not a de Polignac number, because 65610665 - 2²⁰ = 64562089 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6561062 + ... + 6561071.

It is an arithmetic number, because the mean of its divisors is an integer number (19683201).

Almost surely, 2^65610665 is an apocalyptic number.

It is an amenable number.

65610665 is a deficient number, since it is larger than the sum of its proper divisors (13122139).

65610665 is a wasteful number, since it uses less digits than its factorization.

65610665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13122138.

The product of its (nonzero) digits is 32400, while the sum is 35.

The square root of 65610665 is about 8100.0410492787. The cubic root of 65610665 is about 403.3277898440.

Subtracting from 65610665 its reverse (56601656), we obtain a palindrome (9009009).

The spelling of 65610665 in words is "sixty-five million, six hundred ten thousand, six hundred sixty-five".