20426689 has 2 divisors, whose sum is σ = 20426690. Its totient is φ = 20426688.

The previous prime is 20426647. The next prime is 20426711. The reversal of 20426689 is 98662402.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16265089 + 4161600 = 4033^2 + 2040^2 .

It is a cyclic number.

It is not a de Polignac number, because 20426689 - 2⁷ = 20426561 is a prime.

It is not a weakly prime, because it can be changed into another prime (20426389) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10213344 + 10213345.

It is an arithmetic number, because the mean of its divisors is an integer number (10213345).

Almost surely, 2^20426689 is an apocalyptic number.

It is an amenable number.

20426689 is a deficient number, since it is larger than the sum of its proper divisors (1).

20426689 is an equidigital number, since it uses as much as digits as its factorization.

20426689 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 37.

The square root of 20426689 is about 4519.5894725074. The cubic root of 20426689 is about 273.3585479747.

It can be divided in two parts, 20426 and 689, that added together give a triangular number (21115 = T₂₀₅).

The spelling of 20426689 in words is "twenty million, four hundred twenty-six thousand, six hundred eighty-nine".