21404012239 has 4 divisors (see below), whose sum is σ = 21926061360. Its totient is φ = 20881963120.

The previous prime is 21404012237. The next prime is 21404012243. The reversal of 21404012239 is 93221040412.

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 21404012239 - 2¹ = 21404012237 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 (21404012237) 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 3 ways as a sum of consecutive naturals, for example, 261024499 + ... + 261024580.

It is an arithmetic number, because the mean of its divisors is an integer number (5481515340).

Almost surely, 2^21404012239 is an apocalyptic number.

21404012239 is a deficient number, since it is larger than the sum of its proper divisors (522049121).

21404012239 is an equidigital number, since it uses as much as digits as its factorization.

21404012239 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 522049120.

The product of its (nonzero) digits is 3456, while the sum is 28.

The spelling of 21404012239 in words is "twenty-one billion, four hundred four million, twelve thousand, two hundred thirty-nine".