21311341231 has 2 divisors, whose sum is σ = 21311341232. Its totient is φ = 21311341230.

The previous prime is 21311341217. The next prime is 21311341237. The reversal of 21311341231 is 13214311312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21311341231 - 2⁹ = 21311340719 is a prime.

It is a super-2 number, since 2×21311341231² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21311341237) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10655670615 + 10655670616.

It is an arithmetic number, because the mean of its divisors is an integer number (10655670616).

Almost surely, 2^21311341231 is an apocalyptic number.

21311341231 is a deficient number, since it is larger than the sum of its proper divisors (1).

21311341231 is an equidigital number, since it uses as much as digits as its factorization.

21311341231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 432, while the sum is 22.

Adding to 21311341231 its reverse (13214311312), we get a palindrome (34525652543).

The spelling of 21311341231 in words is "twenty-one billion, three hundred eleven million, three hundred forty-one thousand, two hundred thirty-one".