664006 has 16 divisors (see below), whose sum is σ = 1165824. Its totient is φ = 277704.

The previous prime is 663997. The next prime is 664009. The reversal of 664006 is 600466.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664009) by changing a digit.

664006 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 7 ways as a sum of consecutive naturals, for example, 51 + ... + 1153.

It is an arithmetic number, because the mean of its divisors is an integer number (72864).

2⁶⁶⁴⁰⁰⁶ is an apocalyptic number.

664006 is a deficient number, since it is larger than the sum of its proper divisors (501818).

664006 is a wasteful number, since it uses less digits than its factorization.

664006 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1155.

The product of its (nonzero) digits is 864, while the sum is 22.

The square root of 664006 is about 814.8656330954. The cubic root of 664006 is about 87.2416762036.

The spelling of 664006 in words is "six hundred sixty-four thousand, six".