16105609 has 4 divisors (see below), whose sum is σ = 17344516. Its totient is φ = 14866704.

The previous prime is 16105591. The next prime is 16105633. The reversal of 16105609 is 90650161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 90650161 = 7 ⋅12950023.

It can be written as a sum of positive squares in 2 ways, for example, as 1452025 + 14653584 = 1205^2 + 3828^2 .

It is a cyclic number.

It is not a de Polignac number, because 16105609 - 2⁹ = 16105097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16105669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 619434 + ... + 619459.

It is an arithmetic number, because the mean of its divisors is an integer number (4336129).

Almost surely, 2^16105609 is an apocalyptic number.

It is an amenable number.

16105609 is a deficient number, since it is larger than the sum of its proper divisors (1238907).

16105609 is a wasteful number, since it uses less digits than its factorization.

16105609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1238906.

The product of its (nonzero) digits is 1620, while the sum is 28.

The square root of 16105609 is about 4013.1794128845. The cubic root of 16105609 is about 252.5374071299.

It can be divided in two parts, 16 and 105609, that added together give a square (105625 = 325²).

The spelling of 16105609 in words is "sixteen million, one hundred five thousand, six hundred nine".