21243411227 has 2 divisors, whose sum is σ = 21243411228. Its totient is φ = 21243411226.

The previous prime is 21243411109. The next prime is 21243411257. The reversal of 21243411227 is 72211434212.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21243411227 - 2⁸ = 21243410971 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21243411227.

It is not a weakly prime, because it can be changed into another prime (21243411257) 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, 10621705613 + 10621705614.

It is an arithmetic number, because the mean of its divisors is an integer number (10621705614).

Almost surely, 2^21243411227 is an apocalyptic number.

21243411227 is a deficient number, since it is larger than the sum of its proper divisors (1).

21243411227 is an equidigital number, since it uses as much as digits as its factorization.

21243411227 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5376, while the sum is 29.

Adding to 21243411227 its reverse (72211434212), we get a palindrome (93454845439).

The spelling of 21243411227 in words is "twenty-one billion, two hundred forty-three million, four hundred eleven thousand, two hundred twenty-seven".