20209189 has 24 divisors (see below), whose sum is σ = 27300672. Its totient is φ = 14526720.

The previous prime is 20209169. The next prime is 20209199. The reversal of 20209189 is 98190202.

It is not a de Polignac number, because 20209189 - 2⁷ = 20209061 is a prime.

It is a super-2 number, since 2×20209189² = 816822640075442, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 20209189.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20209109) 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, 12237 + ... + 13789.

It is an arithmetic number, because the mean of its divisors is an integer number (1137528).

Almost surely, 2^20209189 is an apocalyptic number.

It is an amenable number.

20209189 is a deficient number, since it is larger than the sum of its proper divisors (7091483).

20209189 is a wasteful number, since it uses less digits than its factorization.

20209189 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1597 (or 1584 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 31.

The square root of 20209189 is about 4495.4631574511. The cubic root of 20209189 is about 272.3848583495.

The spelling of 20209189 in words is "twenty million, two hundred nine thousand, one hundred eighty-nine".