210020002122121 has 4 divisors (see below), whose sum is σ = 213462952976644. Its totient is φ = 206577051267600.

The previous prime is 210020002122101. The next prime is 210020002122169. The reversal of 210020002122121 is 121221200020012.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 53421407910025 + 156598594212096 = 7308995^2 + 12513936^2 .

It is a cyclic number.

It is not a de Polignac number, because 210020002122121 - 2⁵ = 210020002122089 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 210020002122095 and 210020002122104.

It is not an unprimeable number, because it can be changed into a prime (210020002122101) 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, 1721475427170 + ... + 1721475427291.

It is an arithmetic number, because the mean of its divisors is an integer number (53365738244161).

Almost surely, 2^{210020002122121} is an apocalyptic number.

It is an amenable number.

210020002122121 is a deficient number, since it is larger than the sum of its proper divisors (3442950854523).

210020002122121 is an equidigital number, since it uses as much as digits as its factorization.

210020002122121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3442950854522.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 210020002122121 its reverse (121221200020012), we get a palindrome (331241202142133).

The spelling of 210020002122121 in words is "two hundred ten trillion, twenty billion, two million, one hundred twenty-two thousand, one hundred twenty-one".