210121212210121 has 8 divisors (see below), whose sum is σ = 215246653166664. Its totient is φ = 204995796650880.

The previous prime is 210121212210101. The next prime is 210121212210167. The reversal of 210121212210121 is 121012212121012.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 261950499721 + 209859261710400 = 511811^2 + 14486520^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 210121212210121 - 2⁵ = 210121212210089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (210121212210101) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10968355 + ... + 23249671.

It is an arithmetic number, because the mean of its divisors is an integer number (26905831645833).

Almost surely, 2^{210121212210121} is an apocalyptic number.

It is an amenable number.

210121212210121 is a deficient number, since it is larger than the sum of its proper divisors (5125440956543).

210121212210121 is a wasteful number, since it uses less digits than its factorization.

210121212210121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12698651.

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

Adding to 210121212210121 its reverse (121012212121012), we get a palindrome (331133424331133).

The spelling of 210121212210121 in words is "two hundred ten trillion, one hundred twenty-one billion, two hundred twelve million, two hundred ten thousand, one hundred twenty-one".