211120211021221 has 4 divisors (see below), whose sum is σ = 211120345781100. Its totient is φ = 211120076261344.

The previous prime is 211120211021219. The next prime is 211120211021287. The reversal of 211120211021221 is 122120112021112.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 81911749361121 + 129208461660100 = 9050511^2 + 11366990^2 .

It is a cyclic number.

It is not a de Polignac number, because 211120211021221 - 2¹ = 211120211021219 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211120211027221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 65002006 + ... + 68172583.

It is an arithmetic number, because the mean of its divisors is an integer number (52780086445275).

Almost surely, 2^{211120211021221} is an apocalyptic number.

It is an amenable number.

211120211021221 is a deficient number, since it is larger than the sum of its proper divisors (134759879).

211120211021221 is a wasteful number, since it uses less digits than its factorization.

211120211021221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134759878.

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

Adding to 211120211021221 its reverse (122120112021112), we get a palindrome (333240323042333).

The spelling of 211120211021221 in words is "two hundred eleven trillion, one hundred twenty billion, two hundred eleven million, twenty-one thousand, two hundred twenty-one".