20890489 has 2 divisors, whose sum is σ = 20890490. Its totient is φ = 20890488.

The previous prime is 20890453. The next prime is 20890511. The reversal of 20890489 is 98409802.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10778089 + 10112400 = 3283^2 + 3180^2 .

It is a cyclic number.

It is not a de Polignac number, because 20890489 - 2¹⁵ = 20857721 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20890409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10445244 + 10445245.

It is an arithmetic number, because the mean of its divisors is an integer number (10445245).

Almost surely, 2^20890489 is an apocalyptic number.

It is an amenable number.

20890489 is a deficient number, since it is larger than the sum of its proper divisors (1).

20890489 is an equidigital number, since it uses as much as digits as its factorization.

20890489 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 41472, while the sum is 40.

The square root of 20890489 is about 4570.6114470604. The cubic root of 20890489 is about 275.4120061140.

The spelling of 20890489 in words is "twenty million, eight hundred ninety thousand, four hundred eighty-nine".