208999989 has 24 divisors (see below), whose sum is σ = 348708672. Its totient is φ = 119214720.

The previous prime is 208999937. The next prime is 208999991. The reversal of 208999989 is 989999802.

208999989 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 208999989 - 2¹⁵ = 208967221 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (208999289) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 60409 + ... + 63774.

It is an arithmetic number, because the mean of its divisors is an integer number (14529528).

Almost surely, 2^208999989 is an apocalyptic number.

It is an amenable number.

208999989 is a deficient number, since it is larger than the sum of its proper divisors (139708683).

208999989 is a wasteful number, since it uses less digits than its factorization.

208999989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124217 (or 124214 counting only the distinct ones).

The product of its (nonzero) digits is 7558272, while the sum is 63.

The square root of 208999989 is about 14456.8319143580. The cubic root of 208999989 is about 593.4472036286.

It can be divided in two parts, 20 and 8999989, that added together give a palindrome (9000009).

The spelling of 208999989 in words is "two hundred eight million, nine hundred ninety-nine thousand, nine hundred eighty-nine".