1221011120111 has 16 divisors (see below), whose sum is σ = 1240990970688. Its totient is φ = 1201191936000.

The previous prime is 1221011120101. The next prime is 1221011120113. The reversal of 1221011120111 is 1110211101221.

It is a cyclic number.

It is not a de Polignac number, because 1221011120111 - 2¹⁰ = 1221011119087 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 (1221011120113) 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, 45409391 + ... + 45436271.

It is an arithmetic number, because the mean of its divisors is an integer number (77561935668).

Almost surely, 2^{1221011120111} is an apocalyptic number.

1221011120111 is a deficient number, since it is larger than the sum of its proper divisors (19979850577).

1221011120111 is a wasteful number, since it uses less digits than its factorization.

1221011120111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29842.

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 1221011120111 its reverse (1110211101221), we get a palindrome (2331222221332).

The spelling of 1221011120111 in words is "one trillion, two hundred twenty-one billion, eleven million, one hundred twenty thousand, one hundred eleven".