664558 has 8 divisors (see below), whose sum is σ = 1001880. Its totient is φ = 330600.

The previous prime is 664549. The next prime is 664561. The reversal of 664558 is 855466.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 268 + ... + 1183.

It is an arithmetic number, because the mean of its divisors is an integer number (125235).

2⁶⁶⁴⁵⁵⁸ is an apocalyptic number.

664558 is a deficient number, since it is larger than the sum of its proper divisors (337322).

664558 is a wasteful number, since it uses less digits than its factorization.

664558 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1682.

The product of its digits is 28800, while the sum is 34.

The square root of 664558 is about 815.2042688799. The cubic root of 664558 is about 87.2658446935.

It can be divided in two parts, 66 and 4558, that added together give a square (4624 = 68²).

The spelling of 664558 in words is "six hundred sixty-four thousand, five hundred fifty-eight".