100211212121 has 4 divisors (see below), whose sum is σ = 100531376052. Its totient is φ = 99891048192.

The previous prime is 100211212027. The next prime is 100211212151. The reversal of 100211212121 is 121212112001.

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 24355035721 + 75856176400 = 156061^2 + 275420^2 .

It is a cyclic number.

It is not a de Polignac number, because 100211212121 - 2³⁴ = 83031342937 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 100211212096 and 100211212105.

It is not an unprimeable number, because it can be changed into a prime (100211212151) 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, 160081496 + ... + 160082121.

It is an arithmetic number, because the mean of its divisors is an integer number (25132844013).

Almost surely, 2^100211212121 is an apocalyptic number.

It is an amenable number.

100211212121 is a deficient number, since it is larger than the sum of its proper divisors (320163931).

100211212121 is an equidigital number, since it uses as much as digits as its factorization.

100211212121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 320163930.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 100211212121 its reverse (121212112001), we get a palindrome (221423324122).

The spelling of 100211212121 in words is "one hundred billion, two hundred eleven million, two hundred twelve thousand, one hundred twenty-one".