1221011131121 has 8 divisors (see below), whose sum is σ = 1222351463424. Its totient is φ = 1219671530640.

The previous prime is 1221011131097. The next prime is 1221011131141. The reversal of 1221011131121 is 1211311101221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1221011131121 - 2¹⁴ = 1221011114737 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1221011131121.

It is not an unprimeable number, because it can be changed into a prime (1221011131141) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3189791 + ... + 3552011.

It is an arithmetic number, because the mean of its divisors is an integer number (152793932928).

Almost surely, 2^{1221011131121} is an apocalyptic number.

It is an amenable number.

1221011131121 is a deficient number, since it is larger than the sum of its proper divisors (1340332303).

1221011131121 is a wasteful number, since it uses less digits than its factorization.

1221011131121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 365911.

The product of its (nonzero) digits is 24, while the sum is 17.

Adding to 1221011131121 its reverse (1211311101221), we get a palindrome (2432322232342).

The spelling of 1221011131121 in words is "one trillion, two hundred twenty-one billion, eleven million, one hundred thirty-one thousand, one hundred twenty-one".