20168389 has 2 divisors, whose sum is σ = 20168390. Its totient is φ = 20168388.

The previous prime is 20168381. The next prime is 20168411. The reversal of 20168389 is 98386102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19980900 + 187489 = 4470^2 + 433^2 .

It is a cyclic number.

It is not a de Polignac number, because 20168389 - 2³ = 20168381 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20168381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10084194 + 10084195.

It is an arithmetic number, because the mean of its divisors is an integer number (10084195).

Almost surely, 2^20168389 is an apocalyptic number.

It is an amenable number.

20168389 is a deficient number, since it is larger than the sum of its proper divisors (1).

20168389 is an equidigital number, since it uses as much as digits as its factorization.

20168389 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 20168389 is about 4490.9229563643. The cubic root of 20168389 is about 272.2014304141.

The spelling of 20168389 in words is "twenty million, one hundred sixty-eight thousand, three hundred eighty-nine".