1221132111 has 4 divisors (see below), whose sum is σ = 1628176152. Its totient is φ = 814088072.

The previous prime is 1221132041. The next prime is 1221132113. The reversal of 1221132111 is 1112311221.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1221132111 - 2⁹ = 1221131599 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221132113) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 203522016 + ... + 203522021.

It is an arithmetic number, because the mean of its divisors is an integer number (407044038).

Almost surely, 2^1221132111 is an apocalyptic number.

1221132111 is a deficient number, since it is larger than the sum of its proper divisors (407044041).

1221132111 is an equidigital number, since it uses as much as digits as its factorization.

1221132111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 407044040.

The product of its digits is 24, while the sum is 15.

The square root of 1221132111 is about 34944.7007570533. The cubic root of 1221132111 is about 1068.8601455236.

Adding to 1221132111 its reverse (1112311221), we get a palindrome (2333443332).

The spelling of 1221132111 in words is "one billion, two hundred twenty-one million, one hundred thirty-two thousand, one hundred eleven".