16805321773 has 4 divisors (see below), whose sum is σ = 16830823680. Its totient is φ = 16779819868.

The previous prime is 16805321719. The next prime is 16805321801. The reversal of 16805321773 is 37712350861.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 37712350861 = 173501 ⋅217361.

It is a cyclic number.

It is not a de Polignac number, because 16805321773 - 2²¹ = 16803224621 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 (16805321713) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12749965 + ... + 12751282.

It is an arithmetic number, because the mean of its divisors is an integer number (4207705920).

Almost surely, 2^16805321773 is an apocalyptic number.

It is an amenable number.

16805321773 is a deficient number, since it is larger than the sum of its proper divisors (25501907).

16805321773 is an equidigital number, since it uses as much as digits as its factorization.

16805321773 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25501906.

The product of its (nonzero) digits is 211680, while the sum is 43.

The spelling of 16805321773 in words is "sixteen billion, eight hundred five million, three hundred twenty-one thousand, seven hundred seventy-three".