21446317 has 2 divisors, whose sum is σ = 21446318. Its totient is φ = 21446316.

The previous prime is 21446311. The next prime is 21446329. The reversal of 21446317 is 71364412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15848361 + 5597956 = 3981^2 + 2366^2 .

It is a cyclic number.

It is not a de Polignac number, because 21446317 - 2³ = 21446309 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21446311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10723158 + 10723159.

It is an arithmetic number, because the mean of its divisors is an integer number (10723159).

Almost surely, 2^21446317 is an apocalyptic number.

It is an amenable number.

21446317 is a deficient number, since it is larger than the sum of its proper divisors (1).

21446317 is an equidigital number, since it uses as much as digits as its factorization.

21446317 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4032, while the sum is 28.

The square root of 21446317 is about 4631.0168429838. The cubic root of 21446317 is about 277.8332635412.

The spelling of 21446317 in words is "twenty-one million, four hundred forty-six thousand, three hundred seventeen".