11131001221 has 2 divisors, whose sum is σ = 11131001222. Its totient is φ = 11131001220.

The previous prime is 11131001201. The next prime is 11131001257. The reversal of 11131001221 is 12210013111.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8932329121 + 2198672100 = 94511^2 + 46890^2 .

It is a cyclic number.

It is not a de Polignac number, because 11131001221 - 2³³ = 2541066629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11131001201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5565500610 + 5565500611.

It is an arithmetic number, because the mean of its divisors is an integer number (5565500611).

Almost surely, 2^11131001221 is an apocalyptic number.

It is an amenable number.

11131001221 is a deficient number, since it is larger than the sum of its proper divisors (1).

11131001221 is an equidigital number, since it uses as much as digits as its factorization.

11131001221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12, while the sum is 13.

Adding to 11131001221 its reverse (12210013111), we get a palindrome (23341014332).

The spelling of 11131001221 in words is "eleven billion, one hundred thirty-one million, one thousand, two hundred twenty-one".