663399 has 12 divisors (see below), whose sum is σ = 1045512. Its totient is φ = 402000.

The previous prime is 663371. The next prime is 663407. The reversal of 663399 is 993366.

It is not a de Polignac number, because 663399 - 2¹⁷ = 532327 is a prime.

663399 is a lucky number.

It is a zygodrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (663319) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3252 + ... + 3449.

It is an arithmetic number, because the mean of its divisors is an integer number (87126).

2⁶⁶³³⁹⁹ is an apocalyptic number.

663399 is a deficient number, since it is larger than the sum of its proper divisors (382113).

663399 is a wasteful number, since it uses less digits than its factorization.

663399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6718 (or 6715 counting only the distinct ones).

The product of its digits is 26244, while the sum is 36.

The square root of 663399 is about 814.4930938934. The cubic root of 663399 is about 87.2150841537.

The spelling of 663399 in words is "six hundred sixty-three thousand, three hundred ninety-nine".