21222121200101 has 2 divisors, whose sum is σ = 21222121200102. Its totient is φ = 21222121200100.

The previous prime is 21222121200097. The next prime is 21222121200113. The reversal of 21222121200101 is 10100212122212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18547018890625 + 2675102309476 = 4306625^2 + 1635574^2 .

It is a cyclic number.

It is not a de Polignac number, because 21222121200101 - 2² = 21222121200097 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21222121200101.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21222121200001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10611060600050 + 10611060600051.

It is an arithmetic number, because the mean of its divisors is an integer number (10611060600051).

Almost surely, 2^{21222121200101} is an apocalyptic number.

It is an amenable number.

21222121200101 is a deficient number, since it is larger than the sum of its proper divisors (1).

21222121200101 is an equidigital number, since it uses as much as digits as its factorization.

21222121200101 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 17.

Adding to 21222121200101 its reverse (10100212122212), we get a palindrome (31322333322313).

The spelling of 21222121200101 in words is "twenty-one trillion, two hundred twenty-two billion, one hundred twenty-one million, two hundred thousand, one hundred one".