668889996 has 24 divisors (see below), whose sum is σ = 1602926640. Its totient is φ = 216937152.

The previous prime is 668889941. The next prime is 668889997. The reversal of 668889996 is 699988866.

It is a self number, because there is not a number n which added to its sum of digits gives 668889996.

It is not an unprimeable number, because it can be changed into a prime (668889997) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 752811 + ... + 753698.

It is an arithmetic number, because the mean of its divisors is an integer number (66788610).

Almost surely, 2^668889996 is an apocalyptic number.

It is an amenable number.

668889996 is an abundant number, since it is smaller than the sum of its proper divisors (934036644).

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

668889996 is a wasteful number, since it uses less digits than its factorization.

668889996 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1506553 (or 1506551 counting only the distinct ones).

The product of its digits is 80621568, while the sum is 69.

The square root of 668889996 is about 25862.9077251573. The cubic root of 668889996 is about 874.5505156989.

The spelling of 668889996 in words is "six hundred sixty-eight million, eight hundred eighty-nine thousand, nine hundred ninety-six".