664635 has 16 divisors (see below), whose sum is σ = 1082880. Its totient is φ = 348000.

The previous prime is 664633. The next prime is 664661. The reversal of 664635 is 536466.

It is not a de Polignac number, because 664635 - 2¹ = 664633 is a prime.

It is not an unprimeable number, because it can be changed into a prime (664633) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 510 + ... + 1260.

It is an arithmetic number, because the mean of its divisors is an integer number (67680).

2⁶⁶⁴⁶³⁵ is an apocalyptic number.

664635 is a deficient number, since it is larger than the sum of its proper divisors (418245).

664635 is a wasteful number, since it uses less digits than its factorization.

664635 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 818.

The product of its digits is 12960, while the sum is 30.

The square root of 664635 is about 815.2514949388. The cubic root of 664635 is about 87.2692149589.

The spelling of 664635 in words is "six hundred sixty-four thousand, six hundred thirty-five".