201121121 has 4 divisors (see below), whose sum is σ = 201222852. Its totient is φ = 201019392.

The previous prime is 201121117. The next prime is 201121133. The reversal of 201121121 is 121121102.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 121121102 = 2 ⋅60560551.

It can be written as a sum of positive squares in 2 ways, for example, as 105863521 + 95257600 = 10289^2 + 9760^2 .

It is a cyclic number.

It is not a de Polignac number, because 201121121 - 2² = 201121117 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (201121111) 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, 47840 + ... + 51873.

It is an arithmetic number, because the mean of its divisors is an integer number (50305713).

Almost surely, 2^201121121 is an apocalyptic number.

It is an amenable number.

201121121 is a deficient number, since it is larger than the sum of its proper divisors (101731).

201121121 is an equidigital number, since it uses as much as digits as its factorization.

201121121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101730.

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

The square root of 201121121 is about 14181.7178437593. The cubic root of 201121121 is about 585.8942380778.

Adding to 201121121 its reverse (121121102), we get a palindrome (322242223).

It can be divided in two parts, 2011 and 21121, that added together give a palindrome (23132).

The spelling of 201121121 in words is "two hundred one million, one hundred twenty-one thousand, one hundred twenty-one".