210000121 has 4 divisors (see below), whose sum is σ = 210040144. Its totient is φ = 209960100.

The previous prime is 210000113. The next prime is 210000139. The reversal of 210000121 is 121000012.

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 210000121 - 2³ = 210000113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (210000421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10695 + ... + 23116.

It is an arithmetic number, because the mean of its divisors is an integer number (52510036).

Almost surely, 2^210000121 is an apocalyptic number.

It is an amenable number.

210000121 is a deficient number, since it is larger than the sum of its proper divisors (40023).

210000121 is an equidigital number, since it uses as much as digits as its factorization.

210000121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40022.

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

The square root of 210000121 is about 14491.3809210855. The cubic root of 210000121 is about 594.3923094373.

Adding to 210000121 its reverse (121000012), we get a palindrome (331000133).

The spelling of 210000121 in words is "two hundred ten million, one hundred twenty-one", and thus it is an aban number.