21431328839 has 2 divisors, whose sum is σ = 21431328840. Its totient is φ = 21431328838.

The previous prime is 21431328781. The next prime is 21431328857. The reversal of 21431328839 is 93882313412.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21431328839 - 2²⁸ = 21162893383 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21431328839.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21431328739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10715664419 + 10715664420.

It is an arithmetic number, because the mean of its divisors is an integer number (10715664420).

Almost surely, 2^21431328839 is an apocalyptic number.

21431328839 is a deficient number, since it is larger than the sum of its proper divisors (1).

21431328839 is an equidigital number, since it uses as much as digits as its factorization.

21431328839 is an evil number, because the sum of its binary digits is even.

The product of its digits is 248832, while the sum is 44.

The spelling of 21431328839 in words is "twenty-one billion, four hundred thirty-one million, three hundred twenty-eight thousand, eight hundred thirty-nine".