21738323539 has 2 divisors, whose sum is σ = 21738323540. Its totient is φ = 21738323538.

The previous prime is 21738323513. The next prime is 21738323573. The reversal of 21738323539 is 93532383712.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21738323539 - 2²⁹ = 21201452627 is a prime.

It is not a weakly prime, because it can be changed into another prime (21738323599) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10869161769 + 10869161770.

It is an arithmetic number, because the mean of its divisors is an integer number (10869161770).

Almost surely, 2^21738323539 is an apocalyptic number.

21738323539 is a deficient number, since it is larger than the sum of its proper divisors (1).

21738323539 is an equidigital number, since it uses as much as digits as its factorization.

21738323539 is an evil number, because the sum of its binary digits is even.

The product of its digits is 816480, while the sum is 46.

The spelling of 21738323539 in words is "twenty-one billion, seven hundred thirty-eight million, three hundred twenty-three thousand, five hundred thirty-nine".