21202102100213 has 2 divisors, whose sum is σ = 21202102100214. Its totient is φ = 21202102100212.

The previous prime is 21202102100209. The next prime is 21202102100233. The reversal of 21202102100213 is 31200120120212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20362683325009 + 839418775204 = 4512503^2 + 916198^2 .

It is a cyclic number.

It is not a de Polignac number, because 21202102100213 - 2² = 21202102100209 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21202102100191 and 21202102100200.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21202102100233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10601051050106 + 10601051050107.

It is an arithmetic number, because the mean of its divisors is an integer number (10601051050107).

Almost surely, 2^{21202102100213} is an apocalyptic number.

It is an amenable number.

21202102100213 is a deficient number, since it is larger than the sum of its proper divisors (1).

21202102100213 is an equidigital number, since it uses as much as digits as its factorization.

21202102100213 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 21202102100213 its reverse (31200120120212), we get a palindrome (52402222220425).

The spelling of 21202102100213 in words is "twenty-one trillion, two hundred two billion, one hundred two million, one hundred thousand, two hundred thirteen".