16445689 has 4 divisors (see below), whose sum is σ = 17710756. Its totient is φ = 15180624.

The previous prime is 16445677. The next prime is 16445699. The reversal of 16445689 is 98654461.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 9659664 + 6786025 = 3108^2 + 2605^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16445689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16445699) 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, 632514 + ... + 632539.

It is an arithmetic number, because the mean of its divisors is an integer number (4427689).

Almost surely, 2^16445689 is an apocalyptic number.

It is an amenable number.

16445689 is a deficient number, since it is larger than the sum of its proper divisors (1265067).

16445689 is a wasteful number, since it uses less digits than its factorization.

16445689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1265066.

The product of its digits is 207360, while the sum is 43.

The square root of 16445689 is about 4055.3284700502. The cubic root of 16445689 is about 254.3025359496.

The spelling of 16445689 in words is "sixteen million, four hundred forty-five thousand, six hundred eighty-nine".