21243032117 has 2 divisors, whose sum is σ = 21243032118. Its totient is φ = 21243032116.

The previous prime is 21243032087. The next prime is 21243032123. The reversal of 21243032117 is 71123034212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18805733956 + 2437298161 = 137134^2 + 49369^2 .

It is a cyclic number.

It is not a de Polignac number, because 21243032117 - 2⁸ = 21243031861 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21243032197) 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, 10621516058 + 10621516059.

It is an arithmetic number, because the mean of its divisors is an integer number (10621516059).

Almost surely, 2^21243032117 is an apocalyptic number.

It is an amenable number.

21243032117 is a deficient number, since it is larger than the sum of its proper divisors (1).

21243032117 is an equidigital number, since it uses as much as digits as its factorization.

21243032117 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2016, while the sum is 26.

Adding to 21243032117 its reverse (71123034212), we get a palindrome (92366066329).

The spelling of 21243032117 in words is "twenty-one billion, two hundred forty-three million, thirty-two thousand, one hundred seventeen".