6663866 has 8 divisors (see below), whose sum is σ = 10904544. Its totient is φ = 3029020.

The previous prime is 6663863. The next prime is 6663869. The reversal of 6663866 is 6683666.

It is an interprime number because it is at equal distance from previous prime (6663863) and next prime (6663869).

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

It is a super-2 number, since 2×6663866² = 88814220131912, which contains 22 as substring.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (6663863) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 151430 + ... + 151473.

It is an arithmetic number, because the mean of its divisors is an integer number (1363068).

Almost surely, 2^6663866 is an apocalyptic number.

6663866 is a deficient number, since it is larger than the sum of its proper divisors (4240678).

6663866 is a wasteful number, since it uses less digits than its factorization.

6663866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 302916.

The product of its digits is 186624, while the sum is 41.

The square root of 6663866 is about 2581.4464937318. The cubic root of 6663866 is about 188.1808468023.

It can be divided in two parts, 66 and 63866, that multiplied together give a triangular number (4215156 = T₂₉₀₃).

The spelling of 6663866 in words is "six million, six hundred sixty-three thousand, eight hundred sixty-six".