21411317 has 2 divisors, whose sum is σ = 21411318. Its totient is φ = 21411316.

The previous prime is 21411301. The next prime is 21411329. The reversal of 21411317 is 71311412.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12327121 + 9084196 = 3511^2 + 3014^2 .

It is a cyclic number.

It is not a de Polignac number, because 21411317 - 2⁴ = 21411301 is a prime.

It is equal to p_1354331 and since 21411317 and 1354331 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21411337) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10705658 + 10705659.

It is an arithmetic number, because the mean of its divisors is an integer number (10705659).

Almost surely, 2^21411317 is an apocalyptic number.

It is an amenable number.

21411317 is a deficient number, since it is larger than the sum of its proper divisors (1).

21411317 is an equidigital number, since it uses as much as digits as its factorization.

21411317 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 168, while the sum is 20.

The square root of 21411317 is about 4627.2364322563. The cubic root of 21411317 is about 277.6820416335.

Adding to 21411317 its reverse (71311412), we get a palindrome (92722729).

The spelling of 21411317 in words is "twenty-one million, four hundred eleven thousand, three hundred seventeen".