21452393 has 2 divisors, whose sum is σ = 21452394. Its totient is φ = 21452392.

The previous prime is 21452363. The next prime is 21452407. The reversal of 21452393 is 39325412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21409129 + 43264 = 4627^2 + 208^2 .

It is a cyclic number.

It is not a de Polignac number, because 21452393 - 2¹⁰ = 21451369 is a prime.

It is a plaindrome in base 11.

It is not a weakly prime, because it can be changed into another prime (21452363) 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, 10726196 + 10726197.

It is an arithmetic number, because the mean of its divisors is an integer number (10726197).

Almost surely, 2^21452393 is an apocalyptic number.

It is an amenable number.

21452393 is a deficient number, since it is larger than the sum of its proper divisors (1).

21452393 is an equidigital number, since it uses as much as digits as its factorization.

21452393 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6480, while the sum is 29.

The square root of 21452393 is about 4631.6728079604. The cubic root of 21452393 is about 277.8594989008.

The spelling of 21452393 in words is "twenty-one million, four hundred fifty-two thousand, three hundred ninety-three".