206631906 has 48 divisors (see below), whose sum is σ = 473861664. Its totient is φ = 59834112.

The previous prime is 206631883. The next prime is 206631911. The reversal of 206631906 is 609136602.

It is a happy number.

206631906 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11245 + ... + 23231.

It is an arithmetic number, because the mean of its divisors is an integer number (9872118).

Almost surely, 2^206631906 is an apocalyptic number.

206631906 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 206631906, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (236930832).

206631906 is an abundant number, since it is smaller than the sum of its proper divisors (267229758).

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

206631906 is a wasteful number, since it uses less digits than its factorization.

206631906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12035 (or 12022 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 33.

The square root of 206631906 is about 14374.6967272357. The cubic root of 206631906 is about 591.1973253212.

The spelling of 206631906 in words is "two hundred six million, six hundred thirty-one thousand, nine hundred six".