201121112221 has 4 divisors (see below), whose sum is σ = 206026505244. Its totient is φ = 196215719200.

The previous prime is 201121112189. The next prime is 201121112239. The reversal of 201121112221 is 122211121102.

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 36763844121 + 164357268100 = 191739^2 + 405410^2 .

It is a cyclic number.

It is not a de Polignac number, because 201121112221 - 2⁵ = 201121112189 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 201121112195 and 201121112204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201121112261) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2452696450 + ... + 2452696531.

It is an arithmetic number, because the mean of its divisors is an integer number (51506626311).

Almost surely, 2^201121112221 is an apocalyptic number.

It is an amenable number.

201121112221 is a deficient number, since it is larger than the sum of its proper divisors (4905393023).

201121112221 is an equidigital number, since it uses as much as digits as its factorization.

201121112221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4905393022.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 201121112221 its reverse (122211121102), we get a palindrome (323332233323).

The spelling of 201121112221 in words is "two hundred one billion, one hundred twenty-one million, one hundred twelve thousand, two hundred twenty-one".