206642660 has 48 divisors (see below), whose sum is σ = 502951680. Its totient is φ = 69847680.

The previous prime is 206642593. The next prime is 206642677. The reversal of 206642660 is 66246602.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 455 + ... + 20334.

It is an arithmetic number, because the mean of its divisors is an integer number (10478160).

Almost surely, 2^206642660 is an apocalyptic number.

206642660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 206642660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (251475840).

206642660 is an abundant number, since it is smaller than the sum of its proper divisors (296309020).

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

206642660 is a wasteful number, since it uses less digits than its factorization.

206642660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20876 (or 20874 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 32.

The square root of 206642660 is about 14375.0707824344. The cubic root of 206642660 is about 591.2075812813.

The spelling of 206642660 in words is "two hundred six million, six hundred forty-two thousand, six hundred sixty".