21120202200121 has 2 divisors, whose sum is σ = 21120202200122. Its totient is φ = 21120202200120.

The previous prime is 21120202200107. The next prime is 21120202200277. The reversal of 21120202200121 is 12100220202112.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18505577879721 + 2614624320400 = 4301811^2 + 1616980^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21120202200121 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21120202200095 and 21120202200104.

It is not a weakly prime, because it can be changed into another prime (21120202260121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10560101100060 + 10560101100061.

It is an arithmetic number, because the mean of its divisors is an integer number (10560101100061).

Almost surely, 2^{21120202200121} is an apocalyptic number.

It is an amenable number.

21120202200121 is a deficient number, since it is larger than the sum of its proper divisors (1).

21120202200121 is an equidigital number, since it uses as much as digits as its factorization.

21120202200121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21120202200121 its reverse (12100220202112), we get a palindrome (33220422402233).

The spelling of 21120202200121 in words is "twenty-one trillion, one hundred twenty billion, two hundred two million, two hundred thousand, one hundred twenty-one".