1101221111 has 2 divisors, whose sum is σ = 1101221112. Its totient is φ = 1101221110.

The previous prime is 1101221039. The next prime is 1101221113. The reversal of 1101221111 is 1111221011.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1101221111 - 2¹⁸ = 1100958967 is a prime.

Together with 1101221113, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 1101221092 and 1101221101.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1101221113) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 550610555 + 550610556.

It is an arithmetic number, because the mean of its divisors is an integer number (550610556).

Almost surely, 2^1101221111 is an apocalyptic number.

1101221111 is a deficient number, since it is larger than the sum of its proper divisors (1).

1101221111 is an equidigital number, since it uses as much as digits as its factorization.

1101221111 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4, while the sum is 11.

The square root of 1101221111 is about 33184.6517384167. The cubic root of 1101221111 is about 1032.6619525635.

Adding to 1101221111 its reverse (1111221011), we get a palindrome (2212442122).

It can be divided in two parts, 11012 and 21111, that added together give a palindrome (32123).

The spelling of 1101221111 in words is "one billion, one hundred one million, two hundred twenty-one thousand, one hundred eleven".