21475443 has 24 divisors (see below), whose sum is σ = 31979584. Its totient is φ = 12806640.

The previous prime is 21475417. The next prime is 21475451. The reversal of 21475443 is 34457412.

It is not a de Polignac number, because 21475443 - 2⁵ = 21475411 is a prime.

It is a super-2 number, since 2×21475443² = 922389304092498, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21475443.

It is not an unprimeable number, because it can be changed into a prime (21475043) 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 in 23 ways as a sum of consecutive naturals, for example, 23880 + ... + 24762.

Almost surely, 2^21475443 is an apocalyptic number.

21475443 is a deficient number, since it is larger than the sum of its proper divisors (10504141).

21475443 is a wasteful number, since it uses less digits than its factorization.

21475443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 975 (or 964 counting only the distinct ones).

The product of its digits is 13440, while the sum is 30.

The square root of 21475443 is about 4634.1604417629. The cubic root of 21475443 is about 277.9589807153.

It can be divided in two parts, 214 and 75443, that added together give a palindrome (75657).

The spelling of 21475443 in words is "twenty-one million, four hundred seventy-five thousand, four hundred forty-three".