21363543 has 24 divisors (see below), whose sum is σ = 34398000. Its totient is φ = 12697344.

The previous prime is 21363497. The next prime is 21363593. The reversal of 21363543 is 34536312.

It is a happy number.

21363543 is a `hidden beast` number, since 21 + 3 + 635 + 4 + 3 = 666.

It is not a de Polignac number, because 21363543 - 2⁹ = 21363031 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21363593) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 768 + ... + 6581.

It is an arithmetic number, because the mean of its divisors is an integer number (1433250).

Almost surely, 2^21363543 is an apocalyptic number.

21363543 is a deficient number, since it is larger than the sum of its proper divisors (13034457).

21363543 is a wasteful number, since it uses less digits than its factorization.

21363543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7391 (or 7388 counting only the distinct ones).

The product of its digits is 6480, while the sum is 27.

The square root of 21363543 is about 4622.0712889353. The cubic root of 21363543 is about 277.4753618252.

Adding to 21363543 its reverse (34536312), we get a palindrome (55899855).

The spelling of 21363543 in words is "twenty-one million, three hundred sixty-three thousand, five hundred forty-three".