210202111212121 has 12 divisors (see below), whose sum is σ = 244550380206132. Its totient is φ = 180151459369728.

The previous prime is 210202111211977. The next prime is 210202111212131. The reversal of 210202111212121 is 121212111202012.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 178210191512521 + 31991919699600 = 13349539^2 + 5656140^2 .

It is a de Polignac number, because none of the positive numbers 2^k-210202111212121 is a prime.

It is not an unprimeable number, because it can be changed into a prime (210202111212131) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 258862060 + ... + 259672813.

It is an arithmetic number, because the mean of its divisors is an integer number (20379198350511).

Almost surely, 2^{210202111212121} is an apocalyptic number.

It is an amenable number.

210202111212121 is a deficient number, since it is larger than the sum of its proper divisors (34348268994011).

210202111212121 is an equidigital number, since it uses as much as digits as its factorization.

210202111212121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 518543160 (or 518543153 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 210202111212121 its reverse (121212111202012), we get a palindrome (331414222414133).

The spelling of 210202111212121 in words is "two hundred ten trillion, two hundred two billion, one hundred eleven million, two hundred twelve thousand, one hundred twenty-one".