21421424403 has 16 divisors (see below), whose sum is σ = 32829770400. Its totient is φ = 13788502560.

The previous prime is 21421424393. The next prime is 21421424477. The reversal of 21421424403 is 30442412412.

21421424403 is a `hidden beast` number, since 2 + 1 + 4 + 214 + 2 + 440 + 3 = 666.

It is not a de Polignac number, because 21421424403 - 2⁸ = 21421424147 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (21421424903) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13678288 + ... + 13679853.

It is an arithmetic number, because the mean of its divisors is an integer number (2051860650).

Almost surely, 2^21421424403 is an apocalyptic number.

21421424403 is a deficient number, since it is larger than the sum of its proper divisors (11408345997).

21421424403 is a wasteful number, since it uses less digits than its factorization.

21421424403 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27358179 (or 27358173 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 27.

Adding to 21421424403 its reverse (30442412412), we get a palindrome (51863836815).

The spelling of 21421424403 in words is "twenty-one billion, four hundred twenty-one million, four hundred twenty-four thousand, four hundred three".