21231422243 has 2 divisors, whose sum is σ = 21231422244. Its totient is φ = 21231422242.

The previous prime is 21231422237. The next prime is 21231422257. The reversal of 21231422243 is 34222413212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21231422243 - 2⁴ = 21231422227 is a prime.

It is not a weakly prime, because it can be changed into another prime (21231422293) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10615711121 + 10615711122.

It is an arithmetic number, because the mean of its divisors is an integer number (10615711122).

Almost surely, 2^21231422243 is an apocalyptic number.

21231422243 is a deficient number, since it is larger than the sum of its proper divisors (1).

21231422243 is an equidigital number, since it uses as much as digits as its factorization.

21231422243 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4608, while the sum is 26.

Adding to 21231422243 its reverse (34222413212), we get a palindrome (55453835455).

The spelling of 21231422243 in words is "twenty-one billion, two hundred thirty-one million, four hundred twenty-two thousand, two hundred forty-three".