664624 has 10 divisors (see below), whose sum is σ = 1287740. Its totient is φ = 332304.

The previous prime is 664621. The next prime is 664633. The reversal of 664624 is 426466.

It is a super-2 number, since 2×664624² = 883450122752, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 664592 and 664601.

It is not an unprimeable number, because it can be changed into a prime (664621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20754 + ... + 20785.

It is an arithmetic number, because the mean of its divisors is an integer number (128774).

2⁶⁶⁴⁶²⁴ is an apocalyptic number.

It is an amenable number.

664624 is a deficient number, since it is larger than the sum of its proper divisors (623116).

664624 is a wasteful number, since it uses less digits than its factorization.

664624 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41547 (or 41541 counting only the distinct ones).

The product of its digits is 6912, while the sum is 28.

The square root of 664624 is about 815.2447485265. The cubic root of 664624 is about 87.2687335083.

It can be divided in two parts, 66462 and 4, that added together give a palindrome (66466).

The spelling of 664624 in words is "six hundred sixty-four thousand, six hundred twenty-four".