211221221012011 has 16 divisors (see below), whose sum is σ = 249978749360128. Its totient is φ = 174646777406400.

The previous prime is 211221221011921. The next prime is 211221221012029. The reversal of 211221221012011 is 110210122122112.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 211221221012011 - 2¹⁹ = 211221220487723 is a prime.

It is a super-2 number, since 2×211221221012011² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 211221221012011.

It is not an unprimeable number, because it can be changed into a prime (211221221010011) 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, 1554835725 + ... + 1554971566.

It is an arithmetic number, because the mean of its divisors is an integer number (15623671835008).

Almost surely, 2^{211221221012011} is an apocalyptic number.

211221221012011 is a deficient number, since it is larger than the sum of its proper divisors (38757528348117).

211221221012011 is a wasteful number, since it uses less digits than its factorization.

211221221012011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3109807642.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 211221221012011 its reverse (110210122122112), we get a palindrome (321431343134123).

The spelling of 211221221012011 in words is "two hundred eleven trillion, two hundred twenty-one billion, two hundred twenty-one million, twelve thousand, eleven".