6663918 has 16 divisors (see below), whose sum is σ = 13516416. Its totient is φ = 2189880.

The previous prime is 6663911. The next prime is 6663941. The reversal of 6663918 is 8193666.

It is a happy number.

It is a super-2 number, since 2×6663918² = 88815606221448, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6663911) 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, 7396 + ... + 8247.

It is an arithmetic number, because the mean of its divisors is an integer number (844776).

Almost surely, 2^6663918 is an apocalyptic number.

6663918 is an abundant number, since it is smaller than the sum of its proper divisors (6852498).

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

6663918 is a wasteful number, since it uses less digits than its factorization.

6663918 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15719.

The product of its digits is 46656, while the sum is 39.

The square root of 6663918 is about 2581.4565655846. The cubic root of 6663918 is about 188.1813362769.

The spelling of 6663918 in words is "six million, six hundred sixty-three thousand, nine hundred eighteen".