6631666 has 8 divisors (see below), whose sum is σ = 10532700. Its totient is φ = 3120768.

The previous prime is 6631663. The next prime is 6631679. The reversal of 6631666 is 6661366.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 6579225 + 52441 = 2565^2 + 229^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Harshad number since it is a multiple of its sum of digits (34), and also a Moran number because the ratio is a prime number: 195049 = 6631666 / (6 + 6 + 3 + 1 + 6 + 6 + 6).

It is not an unprimeable number, because it can be changed into a prime (6631661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 97491 + ... + 97558.

Almost surely, 2^6631666 is an apocalyptic number.

6631666 is a deficient number, since it is larger than the sum of its proper divisors (3901034).

6631666 is a wasteful number, since it uses less digits than its factorization.

6631666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195068.

The product of its digits is 23328, while the sum is 34.

The square root of 6631666 is about 2575.2021279892. The cubic root of 6631666 is about 187.8772587989.

The spelling of 6631666 in words is "six million, six hundred thirty-one thousand, six hundred sixty-six".