21102110171 has 2 divisors, whose sum is σ = 21102110172. Its totient is φ = 21102110170.

The previous prime is 21102110123. The next prime is 21102110177. The reversal of 21102110171 is 17101120112.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21102110171 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (21102110177) 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 as a sum of consecutive naturals, namely, 10551055085 + 10551055086.

It is an arithmetic number, because the mean of its divisors is an integer number (10551055086).

Almost surely, 2^21102110171 is an apocalyptic number.

21102110171 is a deficient number, since it is larger than the sum of its proper divisors (1).

21102110171 is an equidigital number, since it uses as much as digits as its factorization.

21102110171 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 28, while the sum is 17.

Adding to 21102110171 its reverse (17101120112), we get a palindrome (38203230283).

The spelling of 21102110171 in words is "twenty-one billion, one hundred two million, one hundred ten thousand, one hundred seventy-one".