21204424123 has 8 divisors (see below), whose sum is σ = 21555387216. Its totient is φ = 20856326400.

The previous prime is 21204424103. The next prime is 21204424127. The reversal of 21204424123 is 32142440212.

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

It is a cyclic number.

It is not a de Polignac number, because 21204424123 - 2¹³ = 21204415931 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21204424127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 701418 + ... + 731023.

It is an arithmetic number, because the mean of its divisors is an integer number (2694423402).

Almost surely, 2^21204424123 is an apocalyptic number.

21204424123 is a deficient number, since it is larger than the sum of its proper divisors (350963093).

21204424123 is a wasteful number, since it uses less digits than its factorization.

21204424123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1432685.

The product of its (nonzero) digits is 3072, while the sum is 25.

Adding to 21204424123 its reverse (32142440212), we get a palindrome (53346864335).

The spelling of 21204424123 in words is "twenty-one billion, two hundred four million, four hundred twenty-four thousand, one hundred twenty-three".