21288824805 has 16 divisors (see below), whose sum is σ = 34493287680. Its totient is φ = 11210317248.

The previous prime is 21288824783. The next prime is 21288824839. The reversal of 21288824805 is 50842888212.

It is a happy number.

It is not a de Polignac number, because 21288824805 - 2⁷ = 21288824677 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8981442 + ... + 8983811.

It is an arithmetic number, because the mean of its divisors is an integer number (2155830480).

Almost surely, 2^21288824805 is an apocalyptic number.

It is an amenable number.

21288824805 is a deficient number, since it is larger than the sum of its proper divisors (13204462875).

21288824805 is a wasteful number, since it uses less digits than its factorization.

21288824805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17965340.

The product of its (nonzero) digits is 655360, while the sum is 48.

The spelling of 21288824805 in words is "twenty-one billion, two hundred eighty-eight million, eight hundred twenty-four thousand, eight hundred five".