21112221131 has 2 divisors, whose sum is σ = 21112221132. Its totient is φ = 21112221130.

The previous prime is 21112221101. The next prime is 21112221133. The reversal of 21112221131 is 13112221112.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21112221131 - 2¹⁴ = 21112204747 is a prime.

It is a super-2 number, since 2×21112221131² (a number of 21 digits) contains 22 as substring.

Together with 21112221133, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21112221133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556110565 + 10556110566.

It is an arithmetic number, because the mean of its divisors is an integer number (10556110566).

Almost surely, 2^21112221131 is an apocalyptic number.

21112221131 is a deficient number, since it is larger than the sum of its proper divisors (1).

21112221131 is an equidigital number, since it uses as much as digits as its factorization.

21112221131 is an evil number, because the sum of its binary digits is even.

The product of its digits is 48, while the sum is 17.

Adding to 21112221131 its reverse (13112221112), we get a palindrome (34224442243).

The spelling of 21112221131 in words is "twenty-one billion, one hundred twelve million, two hundred twenty-one thousand, one hundred thirty-one".