20489423 has 2 divisors, whose sum is σ = 20489424. Its totient is φ = 20489422.

The previous prime is 20489387. The next prime is 20489431. The reversal of 20489423 is 32498402.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20489423 - 2¹⁴ = 20473039 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20489423.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20489023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10244711 + 10244712.

It is an arithmetic number, because the mean of its divisors is an integer number (10244712).

Almost surely, 2^20489423 is an apocalyptic number.

20489423 is a deficient number, since it is larger than the sum of its proper divisors (1).

20489423 is an equidigital number, since it uses as much as digits as its factorization.

20489423 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13824, while the sum is 32.

The square root of 20489423 is about 4526.5243841164. The cubic root of 20489423 is about 273.6381062410.

The spelling of 20489423 in words is "twenty million, four hundred eighty-nine thousand, four hundred twenty-three".