21446417 has 2 divisors, whose sum is σ = 21446418. Its totient is φ = 21446416.

The previous prime is 21446407. The next prime is 21446431. The reversal of 21446417 is 71464412.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21446161 + 256 = 4631^2 + 16^2 .

It is a cyclic number.

It is not a de Polignac number, because 21446417 - 2¹⁰ = 21445393 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21446417.

It is not a weakly prime, because it can be changed into another prime (21446407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10723208 + 10723209.

It is an arithmetic number, because the mean of its divisors is an integer number (10723209).

Almost surely, 2^21446417 is an apocalyptic number.

It is an amenable number.

21446417 is a deficient number, since it is larger than the sum of its proper divisors (1).

21446417 is an equidigital number, since it uses as much as digits as its factorization.

21446417 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5376, while the sum is 29.

The square root of 21446417 is about 4631.0276397361. The cubic root of 21446417 is about 277.8336953680.

The spelling of 21446417 in words is "twenty-one million, four hundred forty-six thousand, four hundred seventeen".