21246317 has 2 divisors, whose sum is σ = 21246318. Its totient is φ = 21246316.

The previous prime is 21246307. The next prime is 21246341. The reversal of 21246317 is 71364212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13060996 + 8185321 = 3614^2 + 2861^2 .

It is a cyclic number.

It is not a de Polignac number, because 21246317 - 2¹⁰ = 21245293 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21246307) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10623158 + 10623159.

It is an arithmetic number, because the mean of its divisors is an integer number (10623159).

Almost surely, 2^21246317 is an apocalyptic number.

It is an amenable number.

21246317 is a deficient number, since it is larger than the sum of its proper divisors (1).

21246317 is an equidigital number, since it uses as much as digits as its factorization.

21246317 is an odious number, because the sum of its binary digits is odd.

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

The square root of 21246317 is about 4609.3727338977. The cubic root of 21246317 is about 276.9669099042.

The spelling of 21246317 in words is "twenty-one million, two hundred forty-six thousand, three hundred seventeen".