21234305839 has 2 divisors, whose sum is σ = 21234305840. Its totient is φ = 21234305838.

The previous prime is 21234305837. The next prime is 21234305927. The reversal of 21234305839 is 93850343212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21234305839 - 2¹ = 21234305837 is a prime.

Together with 21234305837, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21234305837) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10617152919 + 10617152920.

It is an arithmetic number, because the mean of its divisors is an integer number (10617152920).

Almost surely, 2^21234305839 is an apocalyptic number.

21234305839 is a deficient number, since it is larger than the sum of its proper divisors (1).

21234305839 is an equidigital number, since it uses as much as digits as its factorization.

21234305839 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 155520, while the sum is 40.

The spelling of 21234305839 in words is "twenty-one billion, two hundred thirty-four million, three hundred five thousand, eight hundred thirty-nine".