1889890209 has 6 divisors (see below), whose sum is σ = 2729841426. Its totient is φ = 1259926800.

The previous prime is 1889890207. The next prime is 1889890213. The reversal of 1889890209 is 9020989881.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 1867536225 + 22353984 = 43215^2 + 4728^2 .

It is not a de Polignac number, because 1889890209 - 2¹ = 1889890207 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1889890201) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 104993892 + ... + 104993909.

It is an arithmetic number, because the mean of its divisors is an integer number (454973571).

Almost surely, 2^1889890209 is an apocalyptic number.

It is an amenable number.

1889890209 is a deficient number, since it is larger than the sum of its proper divisors (839951217).

1889890209 is a wasteful number, since it uses less digits than its factorization.

1889890209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 209987807 (or 209987804 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 54.

The square root of 1889890209 is about 43472.8675037661. The cubic root of 1889890209 is about 1236.3616487364.

The spelling of 1889890209 in words is "one billion, eight hundred eighty-nine million, eight hundred ninety thousand, two hundred nine".