206288091 has 12 divisors (see below), whose sum is σ = 300865968. Its totient is φ = 136189584.

The previous prime is 206288087. The next prime is 206288099. The reversal of 206288091 is 190882602.

206288091 is a `hidden beast` number, since 20 + 628 + 8 + 0 + 9 + 1 = 666.

It is not a de Polignac number, because 206288091 - 2² = 206288087 is a prime.

It is not an unprimeable number, because it can be changed into a prime (206288099) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 110340 + ... + 112193.

It is an arithmetic number, because the mean of its divisors is an integer number (25072164).

Almost surely, 2^206288091 is an apocalyptic number.

206288091 is a deficient number, since it is larger than the sum of its proper divisors (94577877).

206288091 is a wasteful number, since it uses less digits than its factorization.

206288091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 222642 (or 222639 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 206288091 is about 14362.7327135194. The cubic root of 206288091 is about 590.8692453828.

The spelling of 206288091 in words is "two hundred six million, two hundred eighty-eight thousand, ninety-one".