2101122121121 has 4 divisors (see below), whose sum is σ = 2104527506052. Its totient is φ = 2097716736192.

The previous prime is 2101122121117. The next prime is 2101122121151. The reversal of 2101122121121 is 1211212211012.

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 989497720225 + 1111624400896 = 994735^2 + 1054336^2 .

It is a cyclic number.

It is not a de Polignac number, because 2101122121121 - 2² = 2101122121117 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2101122121121.

It is not an unprimeable number, because it can be changed into a prime (2101122121151) 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, 1702691540 + ... + 1702692773.

It is an arithmetic number, because the mean of its divisors is an integer number (526131876513).

Almost surely, 2^{2101122121121} is an apocalyptic number.

It is an amenable number.

2101122121121 is a deficient number, since it is larger than the sum of its proper divisors (3405384931).

2101122121121 is an equidigital number, since it uses as much as digits as its factorization.

2101122121121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3405384930.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 2101122121121 its reverse (1211212211012), we get a palindrome (3312334332133).

The spelling of 2101122121121 in words is "two trillion, one hundred one billion, one hundred twenty-two million, one hundred twenty-one thousand, one hundred twenty-one".