664244 has 18 divisors (see below), whose sum is σ = 1352610. Its totient is φ = 284592.

The previous prime is 664243. The next prime is 664253. The reversal of 664244 is 442466.

It can be written as a sum of positive squares in only one way, i.e., 659344 + 4900 = 812^2 + 70^2 .

It is a super-3 number, since 3×664244³ = 879233395446716352, which contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664243) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1499 + ... + 1890.

It is an arithmetic number, because the mean of its divisors is an integer number (75145).

2⁶⁶⁴²⁴⁴ is an apocalyptic number.

It is an amenable number.

664244 is an abundant number, since it is smaller than the sum of its proper divisors (688366).

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

664244 is a wasteful number, since it uses less digits than its factorization.

664244 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3407 (or 3398 counting only the distinct ones).

The product of its digits is 4608, while the sum is 26.

The square root of 664244 is about 815.0116563584. The cubic root of 664244 is about 87.2520983176.

The spelling of 664244 in words is "six hundred sixty-four thousand, two hundred forty-four".