20423889 has 12 divisors (see below), whose sum is σ = 30298996. Its totient is φ = 13247712.

The previous prime is 20423873. The next prime is 20423891. The reversal of 20423889 is 98832402.

It can be written as a sum of positive squares in 2 ways, for example, as 19289664 + 1134225 = 4392^2 + 1065^2 .

It is not a de Polignac number, because 20423889 - 2⁴ = 20423873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20423899) 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 in 11 ways as a sum of consecutive naturals, for example, 30334 + ... + 30999.

Almost surely, 2^20423889 is an apocalyptic number.

It is an amenable number.

20423889 is a deficient number, since it is larger than the sum of its proper divisors (9875107).

20423889 is a wasteful number, since it uses less digits than its factorization.

20423889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61376 (or 61373 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 20423889 is about 4519.2796992441. The cubic root of 20423889 is about 273.3460571445.

It can be divided in two parts, 20423 and 889, that added together give a palindrome (21312).

The spelling of 20423889 in words is "twenty million, four hundred twenty-three thousand, eight hundred eighty-nine".