1221105021311 has 24 divisors (see below), whose sum is σ = 1423407433680. Its totient is φ = 1044497553792.

The previous prime is 1221105021287. The next prime is 1221105021319. The reversal of 1221105021311 is 1131205011221.

It is not a de Polignac number, because 1221105021311 - 2²² = 1221100827007 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 (1221105021319) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 146008616 + ... + 146016978.

It is an arithmetic number, because the mean of its divisors is an integer number (59308643070).

Almost surely, 2^{1221105021311} is an apocalyptic number.

1221105021311 is a deficient number, since it is larger than the sum of its proper divisors (202302412369).

1221105021311 is an equidigital number, since it uses as much as digits as its factorization.

1221105021311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14183 (or 14176 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 20.

The spelling of 1221105021311 in words is "one trillion, two hundred twenty-one billion, one hundred five million, twenty-one thousand, three hundred eleven".