21448333 has 2 divisors, whose sum is σ = 21448334. Its totient is φ = 21448332.

The previous prime is 21448331. The next prime is 21448337. The reversal of 21448333 is 33384412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21409129 + 39204 = 4627^2 + 198^2 .

It is a cyclic number.

It is not a de Polignac number, because 21448333 - 2¹ = 21448331 is a prime.

Together with 21448331, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21448331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10724166 + 10724167.

It is an arithmetic number, because the mean of its divisors is an integer number (10724167).

Almost surely, 2^21448333 is an apocalyptic number.

It is an amenable number.

21448333 is a deficient number, since it is larger than the sum of its proper divisors (1).

21448333 is an equidigital number, since it uses as much as digits as its factorization.

21448333 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6912, while the sum is 28.

The square root of 21448333 is about 4631.2345006488. The cubic root of 21448333 is about 277.8419689102.

The spelling of 21448333 in words is "twenty-one million, four hundred forty-eight thousand, three hundred thirty-three".