664568268 has 96 divisors (see below), whose sum is σ = 1953025536. Its totient is φ = 171182592.

The previous prime is 664568237. The next prime is 664568269. The reversal of 664568268 is 862865466.

It is a self number, because there is not a number n which added to its sum of digits gives 664568268.

It is not an unprimeable number, because it can be changed into a prime (664568269) 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, 39880 + ... + 54032.

It is an arithmetic number, because the mean of its divisors is an integer number (20344016).

Almost surely, 2^664568268 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 664568268, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (976512768).

664568268 is an abundant number, since it is smaller than the sum of its proper divisors (1288457268).

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

664568268 is a wasteful number, since it uses less digits than its factorization.

664568268 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14223 (or 14221 counting only the distinct ones).

The product of its digits is 3317760, while the sum is 51.

The square root of 664568268 is about 25779.2216329353. The cubic root of 664568268 is about 872.6629413558.

The spelling of 664568268 in words is "six hundred sixty-four million, five hundred sixty-eight thousand, two hundred sixty-eight".