21232420117 has 2 divisors, whose sum is σ = 21232420118. Its totient is φ = 21232420116.

The previous prime is 21232420091. The next prime is 21232420127. The reversal of 21232420117 is 71102423212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18711777681 + 2520642436 = 136791^2 + 50206^2 .

It is a cyclic number.

It is not a de Polignac number, because 21232420117 - 2³¹ = 19084936469 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21232420091 and 21232420100.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21232420127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10616210058 + 10616210059.

It is an arithmetic number, because the mean of its divisors is an integer number (10616210059).

Almost surely, 2^21232420117 is an apocalyptic number.

It is an amenable number.

21232420117 is a deficient number, since it is larger than the sum of its proper divisors (1).

21232420117 is an equidigital number, since it uses as much as digits as its factorization.

21232420117 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1344, while the sum is 25.

Adding to 21232420117 its reverse (71102423212), we get a palindrome (92334843329).

The spelling of 21232420117 in words is "twenty-one billion, two hundred thirty-two million, four hundred twenty thousand, one hundred seventeen".