16544043634 has 4 divisors (see below), whose sum is σ = 24816065454. Its totient is φ = 8272021816.

The previous prime is 16544043623. The next prime is 16544043661. The reversal of 16544043634 is 43634044561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 43634044561 = 5711 ⋅7640351.

It can be written as a sum of positive squares in only one way, i.e., 16534102225 + 9941409 = 128585^2 + 3153^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4136010907 + ... + 4136010910.

Almost surely, 2^16544043634 is an apocalyptic number.

16544043634 is a deficient number, since it is larger than the sum of its proper divisors (8272021820).

16544043634 is an equidigital number, since it uses as much as digits as its factorization.

16544043634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8272021819.

The product of its (nonzero) digits is 414720, while the sum is 40.

The spelling of 16544043634 in words is "sixteen billion, five hundred forty-four million, forty-three thousand, six hundred thirty-four".