20938189 has 8 divisors (see below), whose sum is σ = 21858968. Its totient is φ = 20036160.

The previous prime is 20938117. The next prime is 20938193. The reversal of 20938189 is 98183902.

20938189 = 495² + 496² + ... + 568².

It can be written as a sum of positive squares in 4 ways, for example, as 4656964 + 16281225 = 2158^2 + 4035^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 20938189 - 2⁷ = 20938061 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 (20938199) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2382 + ... + 6895.

It is an arithmetic number, because the mean of its divisors is an integer number (2732371).

Almost surely, 2^20938189 is an apocalyptic number.

It is an amenable number.

20938189 is a deficient number, since it is larger than the sum of its proper divisors (920779).

20938189 is an equidigital number, since it uses as much as digits as its factorization.

20938189 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9375.

The product of its (nonzero) digits is 31104, while the sum is 40.

The square root of 20938189 is about 4575.8265919941. The cubic root of 20938189 is about 275.6214661305.

The spelling of 20938189 in words is "twenty million, nine hundred thirty-eight thousand, one hundred eighty-nine".