201121121220221 has 4 divisors (see below), whose sum is σ = 201551787433152. Its totient is φ = 200690455007292.

The previous prime is 201121121220197. The next prime is 201121121220281. The reversal of 201121121220221 is 122022121121102.

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 a de Polignac number, because none of the positive numbers 2^k-201121121220221 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 201121121220193 and 201121121220202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201121121220281) 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, 215333105765 + ... + 215333106698.

It is an arithmetic number, because the mean of its divisors is an integer number (50387946858288).

Almost surely, 2^{201121121220221} is an apocalyptic number.

It is an amenable number.

201121121220221 is a deficient number, since it is larger than the sum of its proper divisors (430666212931).

201121121220221 is an equidigital number, since it uses as much as digits as its factorization.

201121121220221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 430666212930.

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 201121121220221 its reverse (122022121121102), we get a palindrome (323143242341323).

The spelling of 201121121220221 in words is "two hundred one trillion, one hundred twenty-one billion, one hundred twenty-one million, two hundred twenty thousand, two hundred twenty-one".