16504440561 has 48 divisors (see below), whose sum is σ = 27544458240. Its totient is φ = 9327834720.

The previous prime is 16504440559. The next prime is 16504440593.

16504440561 is a `hidden beast` number, since 1 + 6 + 50 + 4 + 4 + 40 + 561 = 666.

16504440561 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 16504440561 - 2¹ = 16504440559 is a prime.

It is not an unprimeable number, because it can be changed into a prime (16504440521) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 10193410 + ... + 10195028.

It is an arithmetic number, because the mean of its divisors is an integer number (573842880).

Almost surely, 2^16504440561 is an apocalyptic number.

It is an amenable number.

16504440561 is a deficient number, since it is larger than the sum of its proper divisors (11040017679).

16504440561 is a wasteful number, since it uses less digits than its factorization.

16504440561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3306 (or 3303 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 36.

The spelling of 16504440561 in words is "sixteen billion, five hundred four million, four hundred forty thousand, five hundred sixty-one".