2101120212221 has 4 divisors (see below), whose sum is σ = 2101144630332. Its totient is φ = 2101095794112.

The previous prime is 2101120212211. The next prime is 2101120212229. The reversal of 2101120212221 is 1222120211012.

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 1838708880100 + 262411332121 = 1355990^2 + 512261^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2101120212221 is a prime.

It is a super-2 number, since 2×2101120212221² (a number of 25 digits) contains 22 as substring.

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 2101120212221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2101120212229) 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, 12079526 + ... + 12252231.

It is an arithmetic number, because the mean of its divisors is an integer number (525286157583).

Almost surely, 2^{2101120212221} is an apocalyptic number.

It is an amenable number.

2101120212221 is a deficient number, since it is larger than the sum of its proper divisors (24418111).

2101120212221 is an equidigital number, since it uses as much as digits as its factorization.

2101120212221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24418110.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 2101120212221 its reverse (1222120211012), we get a palindrome (3323240423233).

The spelling of 2101120212221 in words is "two trillion, one hundred one billion, one hundred twenty million, two hundred twelve thousand, two hundred twenty-one".