11111221111031 has 2 divisors, whose sum is σ = 11111221111032. Its totient is φ = 11111221111030.

The previous prime is 11111221110917. The next prime is 11111221111057. The reversal of 11111221111031 is 13011112211111.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 11111221111031 - 2⁴² = 6713174599927 is a prime.

It is a super-2 number, since 2×11111221111031² (a number of 27 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11111221111931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5555610555515 + 5555610555516.

It is an arithmetic number, because the mean of its divisors is an integer number (5555610555516).

Almost surely, 2^{11111221111031} is an apocalyptic number.

11111221111031 is a deficient number, since it is larger than the sum of its proper divisors (1).

11111221111031 is an equidigital number, since it uses as much as digits as its factorization.

11111221111031 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 17.

Adding to 11111221111031 its reverse (13011112211111), we get a palindrome (24122333322142).

The spelling of 11111221111031 in words is "eleven trillion, one hundred eleven billion, two hundred twenty-one million, one hundred eleven thousand, thirty-one".