1221202211101 has 4 divisors (see below), whose sum is σ = 1233293322204. Its totient is φ = 1209111100000.

The previous prime is 1221202211087. The next prime is 1221202211129. The reversal of 1221202211101 is 1011122021221.

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

It can be written as a sum of positive squares in 2 ways, for example, as 725443992900 + 495758218201 = 851730^2 + 704101^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221202211101 - 2¹⁷ = 1221202080029 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221202217101) 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, 6045555400 + ... + 6045555601.

It is an arithmetic number, because the mean of its divisors is an integer number (308323330551).

Almost surely, 2^{1221202211101} is an apocalyptic number.

It is an amenable number.

1221202211101 is a deficient number, since it is larger than the sum of its proper divisors (12091111103).

1221202211101 is a wasteful number, since it uses less digits than its factorization.

1221202211101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12091111102.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 1221202211101 its reverse (1011122021221), we get a palindrome (2232324232322).

The spelling of 1221202211101 in words is "one trillion, two hundred twenty-one billion, two hundred two million, two hundred eleven thousand, one hundred one".