21124221331 has 2 divisors, whose sum is σ = 21124221332. Its totient is φ = 21124221330.

The previous prime is 21124221271. The next prime is 21124221343. The reversal of 21124221331 is 13312242112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21124221331 - 2¹¹ = 21124219283 is a prime.

It is a super-2 number, since 2×21124221331² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21124221431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10562110665 + 10562110666.

It is an arithmetic number, because the mean of its divisors is an integer number (10562110666).

Almost surely, 2^21124221331 is an apocalyptic number.

21124221331 is a deficient number, since it is larger than the sum of its proper divisors (1).

21124221331 is an equidigital number, since it uses as much as digits as its factorization.

21124221331 is an evil number, because the sum of its binary digits is even.

The product of its digits is 576, while the sum is 22.

Adding to 21124221331 its reverse (13312242112), we get a palindrome (34436463443).

The spelling of 21124221331 in words is "twenty-one billion, one hundred twenty-four million, two hundred twenty-one thousand, three hundred thirty-one".