665824 has 12 divisors (see below), whose sum is σ = 1310904. Its totient is φ = 332896.

The previous prime is 665813. The next prime is 665843. The reversal of 665824 is 428566.

It is a congruent number.

It is an unprimeable number.

665824 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10372 + ... + 10435.

It is an arithmetic number, because the mean of its divisors is an integer number (109242).

2⁶⁶⁵⁸²⁴ is an apocalyptic number.

It is an amenable number.

665824 is a deficient number, since it is larger than the sum of its proper divisors (645080).

665824 is a wasteful number, since it uses less digits than its factorization.

665824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20817 (or 20809 counting only the distinct ones).

The product of its digits is 11520, while the sum is 31.

The square root of 665824 is about 815.9803919213. The cubic root of 665824 is about 87.3212240979.

The spelling of 665824 in words is "six hundred sixty-five thousand, eight hundred twenty-four".