206391617 has 16 divisors (see below), whose sum is σ = 215930880. Its totient is φ = 197122512.

The previous prime is 206391607. The next prime is 206391631. The reversal of 206391617 is 716193602.

It is not a de Polignac number, because 206391617 - 2⁶ = 206391553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (206391607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 729158 + ... + 729440.

It is an arithmetic number, because the mean of its divisors is an integer number (13495680).

Almost surely, 2^206391617 is an apocalyptic number.

It is an amenable number.

206391617 is a deficient number, since it is larger than the sum of its proper divisors (9539263).

206391617 is a wasteful number, since it uses less digits than its factorization.

206391617 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 652.

The product of its (nonzero) digits is 13608, while the sum is 35.

The square root of 206391617 is about 14366.3362413665. The cubic root of 206391617 is about 590.9680717365.

The spelling of 206391617 in words is "two hundred six million, three hundred ninety-one thousand, six hundred seventeen".