1221102012111 has 4 divisors (see below), whose sum is σ = 1628136016152. Its totient is φ = 814068008072.

The previous prime is 1221102012083. The next prime is 1221102012127. The reversal of 1221102012111 is 1112102011221.

It is a happy number.

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 1221102012111 - 2⁶ = 1221102012047 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221102012191) 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, 203517002016 + ... + 203517002021.

It is an arithmetic number, because the mean of its divisors is an integer number (407034004038).

Almost surely, 2^{1221102012111} is an apocalyptic number.

1221102012111 is a deficient number, since it is larger than the sum of its proper divisors (407034004041).

1221102012111 is an equidigital number, since it uses as much as digits as its factorization.

1221102012111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 407034004040.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 1221102012111 its reverse (1112102011221), we get a palindrome (2333204023332).

The spelling of 1221102012111 in words is "one trillion, two hundred twenty-one billion, one hundred two million, twelve thousand, one hundred eleven".