21794447 has 2 divisors, whose sum is σ = 21794448. Its totient is φ = 21794446.

The previous prime is 21794431. The next prime is 21794453. The reversal of 21794447 is 74449712.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21794447 - 2⁴ = 21794431 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21794447.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21794467) 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, 10897223 + 10897224.

It is an arithmetic number, because the mean of its divisors is an integer number (10897224).

Almost surely, 2^21794447 is an apocalyptic number.

21794447 is a deficient number, since it is larger than the sum of its proper divisors (1).

21794447 is an equidigital number, since it uses as much as digits as its factorization.

21794447 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 56448, while the sum is 38.

The square root of 21794447 is about 4668.4523131333. The cubic root of 21794447 is about 279.3285227984.

The spelling of 21794447 in words is "twenty-one million, seven hundred ninety-four thousand, four hundred forty-seven".