21202111000121 has 4 divisors (see below), whose sum is σ = 21202155794292. Its totient is φ = 21202066205952.

The previous prime is 21202111000097. The next prime is 21202111000129. The reversal of 21202111000121 is 12100011120212.

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 5588193412096 + 15613917588025 = 2363936^2 + 3951445^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21202111000121 is a prime.

It is a super-2 number, since 2×21202111000121² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21202111000096 and 21202111000105.

It is not an unprimeable number, because it can be changed into a prime (21202111000129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21679436 + ... + 22636301.

It is an arithmetic number, because the mean of its divisors is an integer number (5300538948573).

Almost surely, 2^{21202111000121} is an apocalyptic number.

It is an amenable number.

21202111000121 is a deficient number, since it is larger than the sum of its proper divisors (44794171).

21202111000121 is an equidigital number, since it uses as much as digits as its factorization.

21202111000121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44794170.

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

Adding to 21202111000121 its reverse (12100011120212), we get a palindrome (33302122120333).

The spelling of 21202111000121 in words is "twenty-one trillion, two hundred two billion, one hundred eleven million, one hundred twenty-one", and thus it is an aban number.