6566661 has 12 divisors (see below), whose sum is σ = 9897888. Its totient is φ = 4187304.

The previous prime is 6566657. The next prime is 6566663. The reversal of 6566661 is 1666656.

It is not a de Polignac number, because 6566661 - 2² = 6566657 is a prime.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6566663) 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, 15655 + ... + 16068.

It is an arithmetic number, because the mean of its divisors is an integer number (824824).

Almost surely, 2^6566661 is an apocalyptic number.

It is an amenable number.

6566661 is a deficient number, since it is larger than the sum of its proper divisors (3331227).

6566661 is a wasteful number, since it uses less digits than its factorization.

6566661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31752 (or 31749 counting only the distinct ones).

The product of its digits is 38880, while the sum is 36.

The square root of 6566661 is about 2562.5497068350. The cubic root of 6566661 is about 187.2613710955.

It can be divided in two parts, 6566 and 661, that added together give a palindrome (7227).

The spelling of 6566661 in words is "six million, five hundred sixty-six thousand, six hundred sixty-one".