21150403543 has 4 divisors (see below), whose sum is σ = 21150934168. Its totient is φ = 21149872920.

The previous prime is 21150403523. The next prime is 21150403553. The reversal of 21150403543 is 34530405112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21150403543 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21150403523) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 200196 + ... + 287017.

It is an arithmetic number, because the mean of its divisors is an integer number (5287733542).

Almost surely, 2^21150403543 is an apocalyptic number.

21150403543 is a deficient number, since it is larger than the sum of its proper divisors (530625).

21150403543 is an equidigital number, since it uses as much as digits as its factorization.

21150403543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 530624.

The product of its (nonzero) digits is 7200, while the sum is 28.

Adding to 21150403543 its reverse (34530405112), we get a palindrome (55680808655).

The spelling of 21150403543 in words is "twenty-one billion, one hundred fifty million, four hundred three thousand, five hundred forty-three".