1221110212011 has 32 divisors (see below), whose sum is σ = 1680097489920. Its totient is φ = 788311109376.

The previous prime is 1221110211961. The next prime is 1221110212057. The reversal of 1221110212011 is 1102120111221.

It is a happy number.

It is not a de Polignac number, because 1221110212011 - 2⁶ = 1221110211947 is a prime.

It is a super-2 number, since 2×1221110212011² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1221110210011) 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 31 ways as a sum of consecutive naturals, for example, 50578735 + ... + 50602871.

It is an arithmetic number, because the mean of its divisors is an integer number (52503046560).

Almost surely, 2^{1221110212011} is an apocalyptic number.

1221110212011 is a deficient number, since it is larger than the sum of its proper divisors (458987277909).

1221110212011 is a wasteful number, since it uses less digits than its factorization.

1221110212011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26323.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 1221110212011 its reverse (1102120111221), we get a palindrome (2323230323232).

It can be divided in two parts, 1221 and 110212011, that multiplied together give a palindrome (134568865431).

The spelling of 1221110212011 in words is "one trillion, two hundred twenty-one billion, one hundred ten million, two hundred twelve thousand, eleven".