21366344366239 has 2 divisors, whose sum is σ = 21366344366240. Its totient is φ = 21366344366238.

The previous prime is 21366344366177. The next prime is 21366344366321. The reversal of 21366344366239 is 93266344366312.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21366344366239 - 2⁹ = 21366344365727 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21366344366039) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10683172183119 + 10683172183120.

It is an arithmetic number, because the mean of its divisors is an integer number (10683172183120).

Almost surely, 2^{21366344366239} is an apocalyptic number.

21366344366239 is a deficient number, since it is larger than the sum of its proper divisors (1).

21366344366239 is an equidigital number, since it uses as much as digits as its factorization.

21366344366239 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 60466176, while the sum is 58.

The spelling of 21366344366239 in words is "twenty-one trillion, three hundred sixty-six billion, three hundred forty-four million, three hundred sixty-six thousand, two hundred thirty-nine".