21715426423 has 2 divisors, whose sum is σ = 21715426424. Its totient is φ = 21715426422.

The previous prime is 21715426399. The next prime is 21715426441. The reversal of 21715426423 is 32462451712.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21715426423 - 2¹⁷ = 21715295351 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21715426123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10857713211 + 10857713212.

It is an arithmetic number, because the mean of its divisors is an integer number (10857713212).

Almost surely, 2^21715426423 is an apocalyptic number.

21715426423 is a deficient number, since it is larger than the sum of its proper divisors (1).

21715426423 is an equidigital number, since it uses as much as digits as its factorization.

21715426423 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 80640, while the sum is 37.

The spelling of 21715426423 in words is "twenty-one billion, seven hundred fifteen million, four hundred twenty-six thousand, four hundred twenty-three".