21010202002171 has 2 divisors, whose sum is σ = 21010202002172. Its totient is φ = 21010202002170.

The previous prime is 21010202002147. The next prime is 21010202002219. The reversal of 21010202002171 is 17120020201012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21010202002171 - 2³¹ = 21008054518523 is a prime.

It is not a weakly prime, because it can be changed into another prime (21010202002121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505101001085 + 10505101001086.

It is an arithmetic number, because the mean of its divisors is an integer number (10505101001086).

Almost surely, 2^{21010202002171} is an apocalyptic number.

21010202002171 is a deficient number, since it is larger than the sum of its proper divisors (1).

21010202002171 is an equidigital number, since it uses as much as digits as its factorization.

21010202002171 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 112, while the sum is 19.

Adding to 21010202002171 its reverse (17120020201012), we get a palindrome (38130222203183).

The spelling of 21010202002171 in words is "twenty-one trillion, ten billion, two hundred two million, two thousand, one hundred seventy-one".