666441646 has 16 divisors (see below), whose sum is σ = 1080859248. Its totient is φ = 306360000.

The previous prime is 666441631. The next prime is 666441691. The reversal of 666441646 is 646144666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44535 + ... + 57586.

It is an arithmetic number, because the mean of its divisors is an integer number (67553703).

Almost surely, 2^666441646 is an apocalyptic number.

666441646 is a deficient number, since it is larger than the sum of its proper divisors (414417602).

666441646 is a wasteful number, since it uses less digits than its factorization.

666441646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102387.

The product of its digits is 497664, while the sum is 43.

The square root of 666441646 is about 25815.5311004829. The cubic root of 666441646 is about 873.4821668467.

The spelling of 666441646 in words is "six hundred sixty-six million, four hundred forty-one thousand, six hundred forty-six".