210000000121 has 2 divisors, whose sum is σ = 210000000122. Its totient is φ = 210000000120.

The previous prime is 210000000079. The next prime is 210000000169. The reversal of 210000000121 is 121000000012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 199863537721 + 10136462400 = 447061^2 + 100680^2 .

It is a cyclic number.

It is not a de Polignac number, because 210000000121 - 2¹⁷ = 209999869049 is a prime.

It is not a weakly prime, because it can be changed into another prime (210000090121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105000000060 + 105000000061.

It is an arithmetic number, because the mean of its divisors is an integer number (105000000061).

Almost surely, 2^210000000121 is an apocalyptic number.

It is an amenable number.

210000000121 is a deficient number, since it is larger than the sum of its proper divisors (1).

210000000121 is an equidigital number, since it uses as much as digits as its factorization.

210000000121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4, while the sum is 7.

Adding to 210000000121 its reverse (121000000012), we get a palindrome (331000000133).

The spelling of 210000000121 in words is "two hundred ten billion, one hundred twenty-one", and thus it is an aban number.