21449693 has 2 divisors, whose sum is σ = 21449694. Its totient is φ = 21449692.

The previous prime is 21449671. The next prime is 21449711. The reversal of 21449693 is 39694412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12581209 + 8868484 = 3547^2 + 2978^2 .

It is a cyclic number.

It is not a de Polignac number, because 21449693 - 2⁶ = 21449629 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21449633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10724846 + 10724847.

It is an arithmetic number, because the mean of its divisors is an integer number (10724847).

Almost surely, 2^21449693 is an apocalyptic number.

It is an amenable number.

21449693 is a deficient number, since it is larger than the sum of its proper divisors (1).

21449693 is an equidigital number, since it uses as much as digits as its factorization.

21449693 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46656, while the sum is 38.

The square root of 21449693 is about 4631.3813274227. The cubic root of 21449693 is about 277.8478412717.

The spelling of 21449693 in words is "twenty-one million, four hundred forty-nine thousand, six hundred ninety-three".