20969189 has 2 divisors, whose sum is σ = 20969190. Its totient is φ = 20969188.

The previous prime is 20969173. The next prime is 20969197. The reversal of 20969189 is 98196902.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15484225 + 5484964 = 3935^2 + 2342^2 .

It is a cyclic number.

It is not a de Polignac number, because 20969189 - 2⁴ = 20969173 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20969119) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10484594 + 10484595.

It is an arithmetic number, because the mean of its divisors is an integer number (10484595).

Almost surely, 2^20969189 is an apocalyptic number.

It is an amenable number.

20969189 is a deficient number, since it is larger than the sum of its proper divisors (1).

20969189 is an equidigital number, since it uses as much as digits as its factorization.

20969189 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 69984, while the sum is 44.

The square root of 20969189 is about 4579.2127052584. The cubic root of 20969189 is about 275.7574226863.

The spelling of 20969189 in words is "twenty million, nine hundred sixty-nine thousand, one hundred eighty-nine".