201221322121 has 4 divisors (see below), whose sum is σ = 207712332544. Its totient is φ = 194730311700.

The previous prime is 201221322109. The next prime is 201221322131. The reversal of 201221322121 is 121223122102.

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, and also an emirpimes, since its reverse is a distinct semiprime: 121223122102 = 2 ⋅60611561051.

It is a cyclic number.

It is not a de Polignac number, because 201221322121 - 2⁵ = 201221322089 is a prime.

It is a super-2 number, since 2×201221322121² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (201221322131) 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, 3245505165 + ... + 3245505226.

It is an arithmetic number, because the mean of its divisors is an integer number (51928083136).

Almost surely, 2^201221322121 is an apocalyptic number.

It is an amenable number.

201221322121 is a deficient number, since it is larger than the sum of its proper divisors (6491010423).

201221322121 is an equidigital number, since it uses as much as digits as its factorization.

201221322121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6491010422.

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 201221322121 its reverse (121223122102), we get a palindrome (322444444223).

The spelling of 201221322121 in words is "two hundred one billion, two hundred twenty-one million, three hundred twenty-two thousand, one hundred twenty-one".