2121112221101 has 4 divisors (see below), whose sum is σ = 2128351512252. Its totient is φ = 2113872929952.

The previous prime is 2121112221047. The next prime is 2121112221103. The reversal of 2121112221101 is 1011222111212.

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 1074900327076 + 1046211894025 = 1036774^2 + 1022845^2 .

It is a cyclic number.

It is not a de Polignac number, because 2121112221101 - 2³⁸ = 1846234314157 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 2121112221101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121112221103) 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, 3619645136 + ... + 3619645721.

It is an arithmetic number, because the mean of its divisors is an integer number (532087878063).

Almost surely, 2^{2121112221101} is an apocalyptic number.

It is an amenable number.

2121112221101 is a deficient number, since it is larger than the sum of its proper divisors (7239291151).

2121112221101 is an equidigital number, since it uses as much as digits as its factorization.

2121112221101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7239291150.

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

Adding to 2121112221101 its reverse (1011222111212), we get a palindrome (3132334332313).

The spelling of 2121112221101 in words is "two trillion, one hundred twenty-one billion, one hundred twelve million, two hundred twenty-one thousand, one hundred one".