209869128 has 48 divisors (see below), whose sum is σ = 649596480. Its totient is φ = 59962464.

The previous prime is 209869123. The next prime is 209869129. The reversal of 209869128 is 821968902.

It is not an unprimeable number, because it can be changed into a prime (209869123) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 207700 + ... + 208707.

It is an arithmetic number, because the mean of its divisors is an integer number (13533260).

Almost surely, 2^209869128 is an apocalyptic number.

209869128 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

209869128 is an abundant number, since it is smaller than the sum of its proper divisors (439727352).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

209869128 is a wasteful number, since it uses less digits than its factorization.

209869128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 416426 (or 416419 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 45.

The square root of 209869128 is about 14486.8605294591. The cubic root of 209869128 is about 594.2686945455.

The spelling of 209869128 in words is "two hundred nine million, eight hundred sixty-nine thousand, one hundred twenty-eight".