21345320443439 has 2 divisors, whose sum is σ = 21345320443440. Its totient is φ = 21345320443438.

The previous prime is 21345320443373. The next prime is 21345320443477. The reversal of 21345320443439 is 93434402354312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21345320443439 - 2¹⁶ = 21345320377903 is a prime.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 21345320443393 and 21345320443402.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21345320473439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10672660221719 + 10672660221720.

It is an arithmetic number, because the mean of its divisors is an integer number (10672660221720).

Almost surely, 2^{21345320443439} is an apocalyptic number.

21345320443439 is a deficient number, since it is larger than the sum of its proper divisors (1).

21345320443439 is an equidigital number, since it uses as much as digits as its factorization.

21345320443439 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3732480, while the sum is 47.

The spelling of 21345320443439 in words is "twenty-one trillion, three hundred forty-five billion, three hundred twenty million, four hundred forty-three thousand, four hundred thirty-nine".