1221242311311 has 16 divisors (see below), whose sum is σ = 1780571837568. Its totient is φ = 738388778400.

The previous prime is 1221242311301. The next prime is 1221242311411. The reversal of 1221242311311 is 1131132421221.

It is not a de Polignac number, because 1221242311311 - 2¹⁷ = 1221242180239 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221242311301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 43937821 + ... + 43965606.

It is an arithmetic number, because the mean of its divisors is an integer number (111285739848).

Almost surely, 2^{1221242311311} is an apocalyptic number.

1221242311311 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1221242311311 is a deficient number, since it is larger than the sum of its proper divisors (559329526257).

1221242311311 is a wasteful number, since it uses less digits than its factorization.

1221242311311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87903862.

The product of its digits is 576, while the sum is 24.

Adding to 1221242311311 its reverse (1131132421221), we get a palindrome (2352374732532).

The spelling of 1221242311311 in words is "one trillion, two hundred twenty-one billion, two hundred forty-two million, three hundred eleven thousand, three hundred eleven".