21769320805 has 8 divisors (see below), whose sum is σ = 26965868544. Its totient is φ = 16853667600.

The previous prime is 21769320799. The next prime is 21769320809. The reversal of 21769320805 is 50802396712.

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

It is not a de Polignac number, because 21769320805 - 2⁵ = 21769320773 is a prime.

It is a super-2 number, since 2×21769320805² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21769320809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 70223461 + ... + 70223770.

It is an arithmetic number, because the mean of its divisors is an integer number (3370733568).

Almost surely, 2^21769320805 is an apocalyptic number.

It is an amenable number.

21769320805 is a deficient number, since it is larger than the sum of its proper divisors (5196547739).

21769320805 is a wasteful number, since it uses less digits than its factorization.

21769320805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140447267.

The product of its (nonzero) digits is 181440, while the sum is 43.

The spelling of 21769320805 in words is "twenty-one billion, seven hundred sixty-nine million, three hundred twenty thousand, eight hundred five".