201111121212221 has 4 divisors (see below), whose sum is σ = 219393950413344. Its totient is φ = 182828292011100.

The previous prime is 201111121212181. The next prime is 201111121212247. The reversal of 201111121212221 is 122212121111102.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 201111121212221 - 2²² = 201111117017917 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 201111121212193 and 201111121212202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201111121412221) 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, 9141414600545 + ... + 9141414600566.

It is an arithmetic number, because the mean of its divisors is an integer number (54848487603336).

Almost surely, 2^{201111121212221} is an apocalyptic number.

It is an amenable number.

201111121212221 is a deficient number, since it is larger than the sum of its proper divisors (18282829201123).

201111121212221 is a wasteful number, since it uses less digits than its factorization.

201111121212221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18282829201122.

The product of its (nonzero) digits is 64, while the sum is 20.

Adding to 201111121212221 its reverse (122212121111102), we get a palindrome (323323242323323).

The spelling of 201111121212221 in words is "two hundred one trillion, one hundred eleven billion, one hundred twenty-one million, two hundred twelve thousand, two hundred twenty-one".