221110121 has 4 divisors (see below), whose sum is σ = 221426244. Its totient is φ = 220794000.

The previous prime is 221110103. The next prime is 221110129. The reversal of 221110121 is 121011122.

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 196000000 + 25110121 = 14000^2 + 5011^2 .

It is a cyclic number.

It is not a de Polignac number, because 221110121 - 2¹⁴ = 221093737 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221110129) 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, 157010 + ... + 158411.

It is an arithmetic number, because the mean of its divisors is an integer number (55356561).

Almost surely, 2^221110121 is an apocalyptic number.

It is an amenable number.

221110121 is a deficient number, since it is larger than the sum of its proper divisors (316123).

221110121 is an equidigital number, since it uses as much as digits as its factorization.

221110121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 316122.

The product of its (nonzero) digits is 8, while the sum is 11.

The square root of 221110121 is about 14869.7720560875. The cubic root of 221110121 is about 604.6947630404.

Adding to 221110121 its reverse (121011122), we get a palindrome (342121243).

It can be divided in two parts, 2211101 and 21, that added together give a palindrome (2211122).

The spelling of 221110121 in words is "two hundred twenty-one million, one hundred ten thousand, one hundred twenty-one".