2100111122121 has 4 divisors (see below), whose sum is σ = 2800148162832. Its totient is φ = 1400074081412.

The previous prime is 2100111122111. The next prime is 2100111122147. The reversal of 2100111122121 is 1212211110012.

It is a happy number.

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 2100111122121 - 2⁷ = 2100111121993 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 2100111122121.

It is not an unprimeable number, because it can be changed into a prime (2100111122111) 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, 350018520351 + ... + 350018520356.

It is an arithmetic number, because the mean of its divisors is an integer number (700037040708).

Almost surely, 2^{2100111122121} is an apocalyptic number.

It is an amenable number.

2100111122121 is a deficient number, since it is larger than the sum of its proper divisors (700037040711).

2100111122121 is an equidigital number, since it uses as much as digits as its factorization.

2100111122121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 700037040710.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 2100111122121 its reverse (1212211110012), we get a palindrome (3312322232133).

The spelling of 2100111122121 in words is "two trillion, one hundred billion, one hundred eleven million, one hundred twenty-two thousand, one hundred twenty-one".