210221121121 has 4 divisors (see below), whose sum is σ = 229332132144. Its totient is φ = 191110110100.

The previous prime is 210221121059. The next prime is 210221121137. The reversal of 210221121121 is 121121122012.

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 not a de Polignac number, because 210221121121 - 2⁹ = 210221120609 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 210221121095 and 210221121104.

It is not an unprimeable number, because it can be changed into a prime (210221121161) 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, 9555505495 + ... + 9555505516.

It is an arithmetic number, because the mean of its divisors is an integer number (57333033036).

Almost surely, 2^210221121121 is an apocalyptic number.

It is an amenable number.

210221121121 is a deficient number, since it is larger than the sum of its proper divisors (19111011023).

210221121121 is a wasteful number, since it uses less digits than its factorization.

210221121121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19111011022.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 210221121121 its reverse (121121122012), we get a palindrome (331342243133).

The spelling of 210221121121 in words is "two hundred ten billion, two hundred twenty-one million, one hundred twenty-one thousand, one hundred twenty-one".