65665567 has 4 divisors (see below), whose sum is σ = 71635176. Its totient is φ = 59695960.

The previous prime is 65665549. The next prime is 65665573. The reversal of 65665567 is 76556656.

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

It is a cyclic number.

It is not a de Polignac number, because 65665567 - 2¹⁵ = 65632799 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65665517) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2984788 + ... + 2984809.

It is an arithmetic number, because the mean of its divisors is an integer number (17908794).

Almost surely, 2^65665567 is an apocalyptic number.

65665567 is a deficient number, since it is larger than the sum of its proper divisors (5969609).

65665567 is a wasteful number, since it uses less digits than its factorization.

65665567 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5969608.

The product of its digits is 1134000, while the sum is 46.

The square root of 65665567 is about 8103.4293357812. The cubic root of 65665567 is about 403.4402579859.

The spelling of 65665567 in words is "sixty-five million, six hundred sixty-five thousand, five hundred sixty-seven".