21327445439 has 4 divisors (see below), whose sum is σ = 21327884256. Its totient is φ = 21327006624.

The previous prime is 21327445423. The next prime is 21327445459. The reversal of 21327445439 is 93454472312.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21327445439 - 2⁴ = 21327445423 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21327445439.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21327445409) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 135914 + ... + 247239.

It is an arithmetic number, because the mean of its divisors is an integer number (5331971064).

Almost surely, 2^21327445439 is an apocalyptic number.

21327445439 is a deficient number, since it is larger than the sum of its proper divisors (438817).

21327445439 is an equidigital number, since it uses as much as digits as its factorization.

21327445439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 438816.

The product of its digits is 725760, while the sum is 44.

The spelling of 21327445439 in words is "twenty-one billion, three hundred twenty-seven million, four hundred forty-five thousand, four hundred thirty-nine".