263664 has 30 divisors (see below), whose sum is σ = 738296. Its totient is φ = 87840.

The previous prime is 263657. The next prime is 263677. The reversal of 263664 is 466362.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

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

It is a congruent number.

It is an unprimeable number.

263664 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 772 + ... + 1059.

2²⁶³⁶⁶⁴ is an apocalyptic number.

263664 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

263664 is an abundant number, since it is smaller than the sum of its proper divisors (474632).

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

263664 is a wasteful number, since it uses less digits than its factorization.

263664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1845 (or 1836 counting only the distinct ones).

The product of its digits is 5184, while the sum is 27.

The square root of 263664 is about 513.4822294880. The cubic root of 263664 is about 64.1234596030.

The spelling of 263664 in words is "two hundred sixty-three thousand, six hundred sixty-four".