11111221213 has 2 divisors, whose sum is σ = 11111221214. Its totient is φ = 11111221212.

The previous prime is 11111221201. The next prime is 11111221217. The reversal of 11111221213 is 31212211111.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10971934009 + 139287204 = 104747^2 + 11802^2 .

It is a cyclic number.

It is not a de Polignac number, because 11111221213 - 2¹³ = 11111213021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11111221217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5555610606 + 5555610607.

It is an arithmetic number, because the mean of its divisors is an integer number (5555610607).

Almost surely, 2^11111221213 is an apocalyptic number.

It is an amenable number.

11111221213 is a deficient number, since it is larger than the sum of its proper divisors (1).

11111221213 is an equidigital number, since it uses as much as digits as its factorization.

11111221213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 24, while the sum is 16.

Adding to 11111221213 its reverse (31212211111), we get a palindrome (42323432324).

It can be divided in two parts, 11111 and 221213, that added together give a square (232324 = 482²).

The spelling of 11111221213 in words is "eleven billion, one hundred eleven million, two hundred twenty-one thousand, two hundred thirteen".