206440217 has 4 divisors (see below), whose sum is σ = 208759860. Its totient is φ = 204120576.

The previous prime is 206440211. The next prime is 206440219. The reversal of 206440217 is 712044602.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 22458121 + 183982096 = 4739^2 + 13564^2 .

It is a cyclic number.

It is not a de Polignac number, because 206440217 - 2¹⁸ = 206178073 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (206440211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1159688 + ... + 1159865.

It is an arithmetic number, because the mean of its divisors is an integer number (52189965).

Almost surely, 2^206440217 is an apocalyptic number.

It is an amenable number.

206440217 is a deficient number, since it is larger than the sum of its proper divisors (2319643).

206440217 is an equidigital number, since it uses as much as digits as its factorization.

206440217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2319642.

The product of its (nonzero) digits is 2688, while the sum is 26.

The square root of 206440217 is about 14368.0275960203. The cubic root of 206440217 is about 591.0144541020.

Adding to 206440217 its reverse (712044602), we get a palindrome (918484819).

The spelling of 206440217 in words is "two hundred six million, four hundred forty thousand, two hundred seventeen".