21432178805 has 8 divisors (see below), whose sum is σ = 25750888632. Its totient is φ = 17124227008.

The previous prime is 21432178759. The next prime is 21432178877. The reversal of 21432178805 is 50887123412.

It can be written as a sum of positive squares in 4 ways, for example, as 4026917764 + 17405261041 = 63458^2 + 131929^2 .

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 21432178805 - 2²⁴ = 21415401589 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2685122 + ... + 2693091.

It is an arithmetic number, because the mean of its divisors is an integer number (3218861079).

Almost surely, 2^21432178805 is an apocalyptic number.

It is an amenable number.

21432178805 is a deficient number, since it is larger than the sum of its proper divisors (4318709827).

21432178805 is an equidigital number, since it uses as much as digits as its factorization.

21432178805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5379015.

The product of its (nonzero) digits is 107520, while the sum is 41.

The spelling of 21432178805 in words is "twenty-one billion, four hundred thirty-two million, one hundred seventy-eight thousand, eight hundred five".