669399993966 has 64 divisors (see below), whose sum is σ = 1469095729920. Its totient is φ = 201659151360.

The previous prime is 669399993937. The next prime is 669399994001.

669399993966 is nontrivially palindromic in base 10.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8250750 + ... + 8331486.

It is an arithmetic number, because the mean of its divisors is an integer number (22954620780).

Almost surely, 2^669399993966 is an apocalyptic number.

669399993966 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

669399993966 is an abundant number, since it is smaller than the sum of its proper divisors (799695735954).

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

669399993966 is a wasteful number, since it uses less digits than its factorization.

669399993966 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81489.

The product of its digits is 6198727824, while the sum is 84.

The spelling of 669399993966 in words is "six hundred sixty-nine billion, three hundred ninety-nine million, nine hundred ninety-three thousand, nine hundred sixty-six".