21424403423 has 8 divisors (see below), whose sum is σ = 22359395328. Its totient is φ = 20489702904.

The previous prime is 21424403419. The next prime is 21424403453. The reversal of 21424403423 is 32430442412.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21424403423 - 2² = 21424403419 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 (21424403453) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 84686 + ... + 223652.

It is an arithmetic number, because the mean of its divisors is an integer number (2794924416).

Almost surely, 2^21424403423 is an apocalyptic number.

21424403423 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

21424403423 is a deficient number, since it is larger than the sum of its proper divisors (934991905).

21424403423 is a wasteful number, since it uses less digits than its factorization.

21424403423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145693.

The product of its (nonzero) digits is 18432, while the sum is 29.

Adding to 21424403423 its reverse (32430442412), we get a palindrome (53854845835).

The spelling of 21424403423 in words is "twenty-one billion, four hundred twenty-four million, four hundred three thousand, four hundred twenty-three".