3663999 has 12 divisors (see below), whose sum is σ = 5435976. Its totient is φ = 2376432.

The previous prime is 3663971. The next prime is 3664013. The reversal of 3663999 is 9993663.

3663999 is a `hidden beast` number, since 3 + 6 + 639 + 9 + 9 = 666.

It is not a de Polignac number, because 3663999 - 2⁸ = 3663743 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3663929) 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, 5169 + ... + 5834.

It is an arithmetic number, because the mean of its divisors is an integer number (452998).

Almost surely, 2^3663999 is an apocalyptic number.

3663999 is a deficient number, since it is larger than the sum of its proper divisors (1771977).

3663999 is a wasteful number, since it uses less digits than its factorization.

3663999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11046 (or 11043 counting only the distinct ones).

The product of its digits is 236196, while the sum is 45.

The square root of 3663999 is about 1914.1575170294. The cubic root of 3663999 is about 154.1647615380.

The spelling of 3663999 in words is "three million, six hundred sixty-three thousand, nine hundred ninety-nine".