663888 has 20 divisors (see below), whose sum is σ = 1715168. Its totient is φ = 221280.

The previous prime is 663881. The next prime is 663893. The reversal of 663888 is 888366.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (663881) by changing a digit.

663888 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 3 ways as a sum of consecutive naturals, for example, 6868 + ... + 6963.

2⁶⁶³⁸⁸⁸ is an apocalyptic number.

It is an amenable number.

663888 is an abundant number, since it is smaller than the sum of its proper divisors (1051280).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

663888 is a wasteful number, since it uses less digits than its factorization.

663888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13842 (or 13836 counting only the distinct ones).

The product of its digits is 55296, while the sum is 39.

The square root of 663888 is about 814.7932253032. The cubic root of 663888 is about 87.2365080136.

It can be divided in two parts, 663 and 888, that added together give a palindrome (1551).

The spelling of 663888 in words is "six hundred sixty-three thousand, eight hundred eighty-eight".