1221101102011 has 4 divisors (see below), whose sum is σ = 1395544116592. Its totient is φ = 1046658087432.

The previous prime is 1221101101991. The next prime is 1221101102027. The reversal of 1221101102011 is 1102011011221.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1221101102011 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221101101982 and 1221101102000.

It is not an unprimeable number, because it can be changed into a prime (1221101102051) 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, 87221507280 + ... + 87221507293.

It is an arithmetic number, because the mean of its divisors is an integer number (348886029148).

Almost surely, 2^{1221101102011} is an apocalyptic number.

1221101102011 is a deficient number, since it is larger than the sum of its proper divisors (174443014581).

1221101102011 is an equidigital number, since it uses as much as digits as its factorization.

1221101102011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174443014580.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 1221101102011 its reverse (1102011011221), we get a palindrome (2323112113232).

The spelling of 1221101102011 in words is "one trillion, two hundred twenty-one billion, one hundred one million, one hundred two thousand, eleven".