209120989 has 8 divisors (see below), whose sum is σ = 260722368. Its totient is φ = 162951360.

The previous prime is 209120981. The next prime is 209120999. The reversal of 209120989 is 989021902.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 209120989 - 2³ = 209120981 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209120981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1357852 + ... + 1358005.

It is an arithmetic number, because the mean of its divisors is an integer number (32590296).

Almost surely, 2^209120989 is an apocalyptic number.

It is an amenable number.

209120989 is a deficient number, since it is larger than the sum of its proper divisors (51601379).

209120989 is a wasteful number, since it uses less digits than its factorization.

209120989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2715875.

The product of its (nonzero) digits is 23328, while the sum is 40.

The square root of 209120989 is about 14461.0161814445. The cubic root of 209120989 is about 593.5617064394.

The spelling of 209120989 in words is "two hundred nine million, one hundred twenty thousand, nine hundred eighty-nine".