20646426439 has 2 divisors, whose sum is σ = 20646426440. Its totient is φ = 20646426438.

The previous prime is 20646426421. The next prime is 20646426481. The reversal of 20646426439 is 93462464602.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20646426439 - 2¹⁵ = 20646393671 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20646426139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10323213219 + 10323213220.

It is an arithmetic number, because the mean of its divisors is an integer number (10323213220).

Almost surely, 2^20646426439 is an apocalyptic number.

20646426439 is a deficient number, since it is larger than the sum of its proper divisors (1).

20646426439 is an equidigital number, since it uses as much as digits as its factorization.

20646426439 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1492992, while the sum is 46.

It can be divided in two parts, 206464 and 26439, that added together give a triangular number (232903 = T₆₈₂).

The spelling of 20646426439 in words is "twenty billion, six hundred forty-six million, four hundred twenty-six thousand, four hundred thirty-nine".