11111210211281 has 2 divisors, whose sum is σ = 11111210211282. Its totient is φ = 11111210211280.

The previous prime is 11111210211109. The next prime is 11111210211323. The reversal of 11111210211281 is 18211201211111.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9255948284881 + 1855261926400 = 3042359^2 + 1362080^2 .

It is a cyclic number.

It is not a de Polignac number, because 11111210211281 - 2¹⁸ = 11111209949137 is a prime.

It is a super-2 number, since 2×11111210211281² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (11111210210281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5555605105640 + 5555605105641.

It is an arithmetic number, because the mean of its divisors is an integer number (5555605105641).

Almost surely, 2^{11111210211281} is an apocalyptic number.

It is an amenable number.

11111210211281 is a deficient number, since it is larger than the sum of its proper divisors (1).

11111210211281 is an equidigital number, since it uses as much as digits as its factorization.

11111210211281 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 23.

Adding to 11111210211281 its reverse (18211201211111), we get a palindrome (29322411422392).

The spelling of 11111210211281 in words is "eleven trillion, one hundred eleven billion, two hundred ten million, two hundred eleven thousand, two hundred eighty-one".