16428389 has 4 divisors (see below), whose sum is σ = 16445100. Its totient is φ = 16411680.

The previous prime is 16428359. The next prime is 16428403. The reversal of 16428389 is 98382461.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98382461 = 853 ⋅115337.

It can be written as a sum of positive squares in 2 ways, for example, as 15760900 + 667489 = 3970^2 + 817^2 .

It is a cyclic number.

It is not a de Polignac number, because 16428389 - 2⁸ = 16428133 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 (16428319) 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, 6782 + ... + 8879.

It is an arithmetic number, because the mean of its divisors is an integer number (4111275).

Almost surely, 2^16428389 is an apocalyptic number.

It is an amenable number.

16428389 is a deficient number, since it is larger than the sum of its proper divisors (16711).

16428389 is a wasteful number, since it uses less digits than its factorization.

16428389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16710.

The product of its digits is 82944, while the sum is 41.

The square root of 16428389 is about 4053.1949126584. The cubic root of 16428389 is about 254.2133336986.

The spelling of 16428389 in words is "sixteen million, four hundred twenty-eight thousand, three hundred eighty-nine".