664956 has 48 divisors (see below), whose sum is σ = 1774080. Its totient is φ = 215280.

The previous prime is 664949. The next prime is 664967. The reversal of 664956 is 659466.

It is a happy number.

664956 is a `hidden beast` number, since 6 + 649 + 5 + 6 = 666.

664956 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a plaindrome in base 14.

It is a self number, because there is not a number n which added to its sum of digits gives 664956.

It is a congruent number.

It is an unprimeable number.

664956 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5011 + ... + 5141.

It is an arithmetic number, because the mean of its divisors is an integer number (36960).

2⁶⁶⁴⁹⁵⁶ 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 664956, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (887040).

664956 is an abundant number, since it is smaller than the sum of its proper divisors (1109124).

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

664956 is a wasteful number, since it uses less digits than its factorization.

664956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191 (or 183 counting only the distinct ones).

The product of its digits is 38880, while the sum is 36.

The square root of 664956 is about 815.4483429378. The cubic root of 664956 is about 87.2832622226.

The spelling of 664956 in words is "six hundred sixty-four thousand, nine hundred fifty-six".