211111022021221 has 16 divisors (see below), whose sum is σ = 255473913150720. Its totient is φ = 170300160656640.

The previous prime is 211111022021219. The next prime is 211111022021267. The reversal of 211111022021221 is 122120220111112.

It is a happy number.

It is not a de Polignac number, because 211111022021221 - 2¹ = 211111022021219 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211111022021281) 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, 38517625 + ... + 43655806.

It is an arithmetic number, because the mean of its divisors is an integer number (15967119571920).

Almost surely, 2^{211111022021221} is an apocalyptic number.

It is an amenable number.

211111022021221 is a deficient number, since it is larger than the sum of its proper divisors (44362891129499).

211111022021221 is a wasteful number, since it uses less digits than its factorization.

211111022021221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82195044.

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

Adding to 211111022021221 its reverse (122120220111112), we get a palindrome (333231242132333).

The spelling of 211111022021221 in words is "two hundred eleven trillion, one hundred eleven billion, twenty-two million, twenty-one thousand, two hundred twenty-one".