208868391 has 24 divisors (see below), whose sum is σ = 311560704. Its totient is φ = 134749440.

The previous prime is 208868377. The next prime is 208868399. The reversal of 208868391 is 193868802.

It is not a de Polignac number, because 208868391 - 2⁶ = 208868327 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (208868399) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 44635 + ... + 49091.

It is an arithmetic number, because the mean of its divisors is an integer number (12981696).

Almost surely, 2^208868391 is an apocalyptic number.

208868391 is a deficient number, since it is larger than the sum of its proper divisors (102692313).

208868391 is a wasteful number, since it uses less digits than its factorization.

208868391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4631 (or 4628 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 45.

The square root of 208868391 is about 14452.2797855563. The cubic root of 208868391 is about 593.3226217048.

The spelling of 208868391 in words is "two hundred eight million, eight hundred sixty-eight thousand, three hundred ninety-one".