665676676566 has 96 divisors (see below), whose sum is σ = 1578913139232. Its totient is φ = 201016442880.

The previous prime is 665676676547. The next prime is 665676676589.

665676676566 is a `hidden beast` number, since 6 + 6 + 56 + 7 + 6 + 6 + 7 + 6 + 566 = 666.

665676676566 is nontrivially palindromic in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 665676676494 and 665676676503.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 181233306 + ... + 181236978.

It is an arithmetic number, because the mean of its divisors is an integer number (16447011867).

Almost surely, 2^665676676566 is an apocalyptic number.

665676676566 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 665676676566, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (789456569616).

665676676566 is an abundant number, since it is smaller than the sum of its proper divisors (913236462666).

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

665676676566 is a wasteful number, since it uses less digits than its factorization.

665676676566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6638 (or 6635 counting only the distinct ones).

The product of its digits is 2057529600, while the sum is 72.

The spelling of 665676676566 in words is "six hundred sixty-five billion, six hundred seventy-six million, six hundred seventy-six thousand, five hundred sixty-six".