11331122011981 has 2 divisors, whose sum is σ = 11331122011982. Its totient is φ = 11331122011980.

The previous prime is 11331122011961. The next prime is 11331122012107. The reversal of 11331122011981 is 18911022113311.

11331122011981 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11317505222500 + 13616789481 = 3364150^2 + 116691^2 .

It is a cyclic number.

It is not a de Polignac number, because 11331122011981 - 2⁵ = 11331122011949 is a prime.

It is a super-2 number, since 2×11331122011981² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11331122011961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5665561005990 + 5665561005991.

It is an arithmetic number, because the mean of its divisors is an integer number (5665561005991).

Almost surely, 2^{11331122011981} is an apocalyptic number.

It is an amenable number.

11331122011981 is a deficient number, since it is larger than the sum of its proper divisors (1).

11331122011981 is an equidigital number, since it uses as much as digits as its factorization.

11331122011981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2592, while the sum is 34.

The spelling of 11331122011981 in words is "eleven trillion, three hundred thirty-one billion, one hundred twenty-two million, eleven thousand, nine hundred eighty-one".