1221101121201 has 16 divisors (see below), whose sum is σ = 1753493292096. Its totient is φ = 751396562496.

The previous prime is 1221101121161. The next prime is 1221101121203. The reversal of 1221101121201 is 1021211011221.

It is a happy number.

It is not a de Polignac number, because 1221101121201 - 2¹⁰ = 1221101120177 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1221101121203) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 452935 + ... + 1627068.

It is an arithmetic number, because the mean of its divisors is an integer number (109593330756).

Almost surely, 2^{1221101121201} is an apocalyptic number.

It is an amenable number.

1221101121201 is a deficient number, since it is larger than the sum of its proper divisors (532392170895).

1221101121201 is a wasteful number, since it uses less digits than its factorization.

1221101121201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2095072.

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

Adding to 1221101121201 its reverse (1021211011221), we get a palindrome (2242312132422).

The spelling of 1221101121201 in words is "one trillion, two hundred twenty-one billion, one hundred one million, one hundred twenty-one thousand, two hundred one".