211201011221 has 4 divisors (see below), whose sum is σ = 213292110444. Its totient is φ = 209109912000.

The previous prime is 211201011191. The next prime is 211201011227. The reversal of 211201011221 is 122110102112.

211201011221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 108313392100 + 102887619121 = 329110^2 + 320761^2 .

It is a cyclic number.

It is not a de Polignac number, because 211201011221 - 2¹⁸ = 211200749077 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 211201011196 and 211201011205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211201011227) 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, 1045549460 + ... + 1045549661.

It is an arithmetic number, because the mean of its divisors is an integer number (53323027611).

Almost surely, 2^211201011221 is an apocalyptic number.

It is an amenable number.

211201011221 is a deficient number, since it is larger than the sum of its proper divisors (2091099223).

211201011221 is a wasteful number, since it uses less digits than its factorization.

211201011221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2091099222.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 211201011221 its reverse (122110102112), we get a palindrome (333311113333).

The spelling of 211201011221 in words is "two hundred eleven billion, two hundred one million, eleven thousand, two hundred twenty-one".