664297956 has 96 divisors (see below), whose sum is σ = 1995418880. Its totient is φ = 187183872.

The previous prime is 664297951. The next prime is 664297961. The reversal of 664297956 is 659792466.

It is an interprime number because it is at equal distance from previous prime (664297951) and next prime (664297961).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (664297951) 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, 49170 + ... + 61206.

Almost surely, 2^664297956 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 664297956, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (997709440).

664297956 is an abundant number, since it is smaller than the sum of its proper divisors (1331120924).

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

664297956 is a wasteful number, since it uses less digits than its factorization.

664297956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12130 (or 12122 counting only the distinct ones).

The product of its digits is 4898880, while the sum is 54.

The square root of 664297956 is about 25773.9782726687. The cubic root of 664297956 is about 872.5446072601.

The spelling of 664297956 in words is "six hundred sixty-four million, two hundred ninety-seven thousand, nine hundred fifty-six".