664580 has 48 divisors (see below), whose sum is σ = 1645056. Its totient is φ = 220800.

The previous prime is 664579. The next prime is 664583. The reversal of 664580 is 85466.

It is a Smith number, since the sum of its digits (29) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (664583) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6530 + ... + 6630.

It is an arithmetic number, because the mean of its divisors is an integer number (34272).

2⁶⁶⁴⁵⁸⁰ 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 664580, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (822528).

664580 is an abundant number, since it is smaller than the sum of its proper divisors (980476).

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

664580 is a wasteful number, since it uses less digits than its factorization.

664580 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164 (or 162 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 29.

The square root of 664580 is about 815.2177623188. The cubic root of 664580 is about 87.2668076530.

The spelling of 664580 in words is "six hundred sixty-four thousand, five hundred eighty".