221201320121 has 16 divisors (see below), whose sum is σ = 230802219648. Its totient is φ = 211836643200.

The previous prime is 221201320111. The next prime is 221201320159. The reversal of 221201320121 is 121023102122.

It is a cyclic number.

It is not a de Polignac number, because 221201320121 - 2⁶ = 221201320057 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 221201320121.

It is not an unprimeable number, because it can be changed into a prime (221201320111) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 352445 + ... + 752741.

It is an arithmetic number, because the mean of its divisors is an integer number (14425138728).

Almost surely, 2^221201320121 is an apocalyptic number.

It is an amenable number.

221201320121 is a deficient number, since it is larger than the sum of its proper divisors (9600899527).

221201320121 is a wasteful number, since it uses less digits than its factorization.

221201320121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 400592.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 221201320121 its reverse (121023102122), we get a palindrome (342224422243).

The spelling of 221201320121 in words is "two hundred twenty-one billion, two hundred one million, three hundred twenty thousand, one hundred twenty-one".