206660646 has 20 divisors (see below), whose sum is σ = 463073292. Its totient is φ = 68886828.

The previous prime is 206660609. The next prime is 206660647. The reversal of 206660646 is 646066602.

It is a self number, because there is not a number n which added to its sum of digits gives 206660646.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (206660647) 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 9 ways as a sum of consecutive naturals, for example, 637680 + ... + 638003.

Almost surely, 2^206660646 is an apocalyptic number.

206660646 is an abundant number, since it is smaller than the sum of its proper divisors (256412646).

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

206660646 is a wasteful number, since it uses less digits than its factorization.

206660646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1275697 (or 1275688 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 36.

The square root of 206660646 is about 14375.6963657417. The cubic root of 206660646 is about 591.2247335173.

It can be divided in two parts, 20 and 6660646, that added together give a palindrome (6660666).

The spelling of 206660646 in words is "two hundred six million, six hundred sixty thousand, six hundred forty-six".