11121881 has 2 divisors, whose sum is σ = 11121882. Its totient is φ = 11121880.

The previous prime is 11121871. The next prime is 11121883. The reversal of 11121881 is 18812111.

11121881 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10995856 + 126025 = 3316^2 + 355^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11121881 is a prime.

It is a super-2 number, since 2×11121881² = 247392473956322, which contains 22 as substring.

Together with 11121883, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (11121883) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5560940 + 5560941.

It is an arithmetic number, because the mean of its divisors is an integer number (5560941).

Almost surely, 2^11121881 is an apocalyptic number.

It is an amenable number.

11121881 is a deficient number, since it is larger than the sum of its proper divisors (1).

11121881 is an equidigital number, since it uses as much as digits as its factorization.

11121881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 128, while the sum is 23.

The square root of 11121881 is about 3334.9484253883. The cubic root of 11121881 is about 223.2163905971.

Adding to 11121881 its reverse (18812111), we get a palindrome (29933992).

The spelling of 11121881 in words is "eleven million, one hundred twenty-one thousand, eight hundred eighty-one".