201106809 has 6 divisors (see below), whose sum is σ = 290487626. Its totient is φ = 134071200.

The previous prime is 201106781. The next prime is 201106819. The reversal of 201106809 is 908601102.

It can be written as a sum of positive squares in only one way, i.e., 156950784 + 44156025 = 12528^2 + 6645^2 .

It is not a de Polignac number, because 201106809 - 2⁵ = 201106777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (201106819) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 11172592 + ... + 11172609.

Almost surely, 2^201106809 is an apocalyptic number.

It is an amenable number.

201106809 is a deficient number, since it is larger than the sum of its proper divisors (89380817).

201106809 is a wasteful number, since it uses less digits than its factorization.

201106809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22345207 (or 22345204 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 201106809 is about 14181.2132414684. The cubic root of 201106809 is about 585.8803401222.

The spelling of 201106809 in words is "two hundred one million, one hundred six thousand, eight hundred nine".