210001212121 has 8 divisors (see below), whose sum is σ = 212968479744. Its totient is φ = 207034208640.

The previous prime is 210001212073. The next prime is 210001212151. The reversal of 210001212121 is 121212100012.

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 210001212121 - 2¹⁷ = 210001081049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (210001212151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1979401 + ... + 2082793.

It is an arithmetic number, because the mean of its divisors is an integer number (26621059968).

Almost surely, 2^210001212121 is an apocalyptic number.

It is an amenable number.

210001212121 is a deficient number, since it is larger than the sum of its proper divisors (2967267623).

210001212121 is a wasteful number, since it uses less digits than its factorization.

210001212121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132071.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 210001212121 its reverse (121212100012), we get a palindrome (331213312133).

It can be divided in two parts, 2100012 and 12121, that multiplied together give a palindrome (25454245452).

The spelling of 210001212121 in words is "two hundred ten billion, one million, two hundred twelve thousand, one hundred twenty-one".