221221121212011 has 16 divisors (see below), whose sum is σ = 301635207212544. Its totient is φ = 144152181671904.

The previous prime is 221221121212001. The next prime is 221221121212019. The reversal of 221221121212011 is 110212121122122.

It is not a de Polignac number, because 221221121212011 - 2⁹ = 221221121211499 is a prime.

It is a super-2 number, since 2×221221121212011² (a number of 29 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (221221121212019) 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, 1036183965 + ... + 1036397438.

It is an arithmetic number, because the mean of its divisors is an integer number (18852200450784).

Almost surely, 2^{221221121212011} is an apocalyptic number.

221221121212011 is a deficient number, since it is larger than the sum of its proper divisors (80414086000533).

221221121212011 is a wasteful number, since it uses less digits than its factorization.

221221121212011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2072582210.

The product of its (nonzero) digits is 128, while the sum is 21.

Adding to 221221121212011 its reverse (110212121122122), we get a palindrome (331433242334133).

The spelling of 221221121212011 in words is "two hundred twenty-one trillion, two hundred twenty-one billion, one hundred twenty-one million, two hundred twelve thousand, eleven".