21043024403 has 4 divisors (see below), whose sum is σ = 21075751368. Its totient is φ = 21010297440.

The previous prime is 21043024391. The next prime is 21043024447. The reversal of 21043024403 is 30442034012.

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

It is a cyclic number.

It is not a de Polignac number, because 21043024403 - 2⁶ = 21043024339 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21043924403) 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, 16362518 + ... + 16363803.

It is an arithmetic number, because the mean of its divisors is an integer number (5268937842).

Almost surely, 2^21043024403 is an apocalyptic number.

21043024403 is a deficient number, since it is larger than the sum of its proper divisors (32726965).

21043024403 is an equidigital number, since it uses as much as digits as its factorization.

21043024403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32726964.

The product of its (nonzero) digits is 2304, while the sum is 23.

Adding to 21043024403 its reverse (30442034012), we get a palindrome (51485058415).

The spelling of 21043024403 in words is "twenty-one billion, forty-three million, twenty-four thousand, four hundred three".