664899 has 8 divisors (see below), whose sum is σ = 891072. Its totient is φ = 441000.

The previous prime is 664891. The next prime is 664933. The reversal of 664899 is 998466.

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

It is not a de Polignac number, because 664899 - 2³ = 664891 is a prime.

It is a plaindrome in base 14.

It is a self number, because there is not a number n which added to its sum of digits gives 664899.

It is not an unprimeable number, because it can be changed into a prime (664891) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 312 + ... + 1194.

It is an arithmetic number, because the mean of its divisors is an integer number (111384).

2⁶⁶⁴⁸⁹⁹ is an apocalyptic number.

664899 is a deficient number, since it is larger than the sum of its proper divisors (226173).

664899 is a wasteful number, since it uses less digits than its factorization.

664899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1137.

The product of its digits is 93312, while the sum is 42.

The square root of 664899 is about 815.4133920902. The cubic root of 664899 is about 87.2807681788.

The spelling of 664899 in words is "six hundred sixty-four thousand, eight hundred ninety-nine".