21203302171 has 2 divisors, whose sum is σ = 21203302172. Its totient is φ = 21203302170.

The previous prime is 21203302163. The next prime is 21203302213. The reversal of 21203302171 is 17120330212.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21203302171 - 2³ = 21203302163 is a prime.

It is not a weakly prime, because it can be changed into another prime (21203372171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10601651085 + 10601651086.

It is an arithmetic number, because the mean of its divisors is an integer number (10601651086).

Almost surely, 2^21203302171 is an apocalyptic number.

21203302171 is a deficient number, since it is larger than the sum of its proper divisors (1).

21203302171 is an equidigital number, since it uses as much as digits as its factorization.

21203302171 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 504, while the sum is 22.

Adding to 21203302171 its reverse (17120330212), we get a palindrome (38323632383).

The spelling of 21203302171 in words is "twenty-one billion, two hundred three million, three hundred two thousand, one hundred seventy-one".