100001212121 has 2 divisors, whose sum is σ = 100001212122. Its totient is φ = 100001212120.

The previous prime is 100001212093. The next prime is 100001212151. The reversal of 100001212121 is 121212100001.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 98166289225 + 1834922896 = 313315^2 + 42836^2 .

It is a cyclic number.

It is not a de Polignac number, because 100001212121 - 2¹⁴ = 100001195737 is a prime.

It is not a weakly prime, because it can be changed into another prime (100001212151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50000606060 + 50000606061.

It is an arithmetic number, because the mean of its divisors is an integer number (50000606061).

Almost surely, 2^100001212121 is an apocalyptic number.

It is an amenable number.

100001212121 is a deficient number, since it is larger than the sum of its proper divisors (1).

100001212121 is an equidigital number, since it uses as much as digits as its factorization.

100001212121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 100001212121 its reverse (121212100001), we get a palindrome (221213312122).

The spelling of 100001212121 in words is "one hundred billion, one million, two hundred twelve thousand, one hundred twenty-one".