211111100221 has 32 divisors (see below), whose sum is σ = 265227982848. Its totient is φ = 163861125120.

The previous prime is 211111100209. The next prime is 211111100243. The reversal of 211111100221 is 122001111112.

It is a happy number.

It is not a de Polignac number, because 211111100221 - 2³¹ = 208963616573 is a prime.

It is a super-3 number, since 3×211111100221³ (a number of 35 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211111100821) 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, 472801 + ... + 803593.

It is an arithmetic number, because the mean of its divisors is an integer number (8288374464).

Almost surely, 2^211111100221 is an apocalyptic number.

It is an amenable number.

211111100221 is a deficient number, since it is larger than the sum of its proper divisors (54116882627).

211111100221 is a wasteful number, since it uses less digits than its factorization.

211111100221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 331021.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 211111100221 its reverse (122001111112), we get a palindrome (333112211333).

The spelling of 211111100221 in words is "two hundred eleven billion, one hundred eleven million, one hundred thousand, two hundred twenty-one".