665238832566 has 64 divisors (see below), whose sum is σ = 1658867351040. Its totient is φ = 172779932160.

The previous prime is 665238832553. The next prime is 665238832567.

665238832566 is nontrivially palindromic in base 10.

665238832566 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665238832567) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13738350 + ... + 13786686.

It is an arithmetic number, because the mean of its divisors is an integer number (25919802360).

Almost surely, 2^665238832566 is an apocalyptic number.

665238832566 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

665238832566 is an abundant number, since it is smaller than the sum of its proper divisors (993628518474).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

665238832566 is a wasteful number, since it uses less digits than its factorization.

665238832566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78149.

The product of its digits is 74649600, while the sum is 60.

The spelling of 665238832566 in words is "six hundred sixty-five billion, two hundred thirty-eight million, eight hundred thirty-two thousand, five hundred sixty-six".