1221113211211 has 16 divisors (see below), whose sum is σ = 1229402851648. Its totient is φ = 1212857712000.

The previous prime is 1221113211193. The next prime is 1221113211217. The reversal of 1221113211211 is 1121123111221.

It is a cyclic number.

It is not a de Polignac number, because 1221113211211 - 2⁵ = 1221113211179 is a prime.

It is a super-2 number, since 2×1221113211211² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221113211217) 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, 123327361 + ... + 123337261.

It is an arithmetic number, because the mean of its divisors is an integer number (76837678228).

Almost surely, 2^{1221113211211} is an apocalyptic number.

1221113211211 is a deficient number, since it is larger than the sum of its proper divisors (8289640437).

1221113211211 is an equidigital number, since it uses as much as digits as its factorization.

1221113211211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11542.

The product of its digits is 48, while the sum is 19.

Adding to 1221113211211 its reverse (1121123111221), we get a palindrome (2342236322432).

The spelling of 1221113211211 in words is "one trillion, two hundred twenty-one billion, one hundred thirteen million, two hundred eleven thousand, two hundred eleven".