206680690 has 8 divisors (see below), whose sum is σ = 372025260. Its totient is φ = 82672272.

The previous prime is 206680687. The next prime is 206680697. The reversal of 206680690 is 96086602.

It can be written as a sum of positive squares in 2 ways, for example, as 185695129 + 20985561 = 13627^2 + 4581^2 .

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

It is a super-2 number, since 2×206680690² = 85433815237752200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (206680697) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 10334025 + ... + 10334044.

Almost surely, 2^206680690 is an apocalyptic number.

206680690 is a deficient number, since it is larger than the sum of its proper divisors (165344570).

206680690 is a wasteful number, since it uses less digits than its factorization.

206680690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20668076.

The product of its (nonzero) digits is 31104, while the sum is 37.

The square root of 206680690 is about 14376.3934976753. The cubic root of 206680690 is about 591.2438471797.

The spelling of 206680690 in words is "two hundred six million, six hundred eighty thousand, six hundred ninety".