21460635605 has 4 divisors (see below), whose sum is σ = 25752762732. Its totient is φ = 17168508480.

The previous prime is 21460635589. The next prime is 21460635611. The reversal of 21460635605 is 50653606412.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 15494772484 + 5965863121 = 124478^2 + 77239^2 .

It is not a de Polignac number, because 21460635605 - 2⁴ = 21460635589 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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, 2146063556 + ... + 2146063565.

It is an arithmetic number, because the mean of its divisors is an integer number (6438190683).

Almost surely, 2^21460635605 is an apocalyptic number.

It is an amenable number.

21460635605 is a deficient number, since it is larger than the sum of its proper divisors (4292127127).

21460635605 is an equidigital number, since it uses as much as digits as its factorization.

21460635605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4292127126.

The product of its (nonzero) digits is 129600, while the sum is 38.

The spelling of 21460635605 in words is "twenty-one billion, four hundred sixty million, six hundred thirty-five thousand, six hundred five".