21338421659 has 2 divisors, whose sum is σ = 21338421660. Its totient is φ = 21338421658.

The previous prime is 21338421583. The next prime is 21338421677. The reversal of 21338421659 is 95612483312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21338421659 - 2¹² = 21338417563 is a prime.

It is not a weakly prime, because it can be changed into another prime (21338421679) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10669210829 + 10669210830.

It is an arithmetic number, because the mean of its divisors is an integer number (10669210830).

Almost surely, 2^21338421659 is an apocalyptic number.

21338421659 is a deficient number, since it is larger than the sum of its proper divisors (1).

21338421659 is an equidigital number, since it uses as much as digits as its factorization.

21338421659 is an evil number, because the sum of its binary digits is even.

The product of its digits is 311040, while the sum is 44.

The spelling of 21338421659 in words is "twenty-one billion, three hundred thirty-eight million, four hundred twenty-one thousand, six hundred fifty-nine".