28409519 has 4 divisors (see below), whose sum is σ = 28633344. Its totient is φ = 28185696.

The previous prime is 28409509. The next prime is 28409569. The reversal of 28409519 is 91590482.

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

It is a cyclic number.

It is not a de Polignac number, because 28409519 - 2¹² = 28405423 is a prime.

It is a super-2 number, since 2×28409519² = 1614201539622722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28409509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 111722 + ... + 111975.

It is an arithmetic number, because the mean of its divisors is an integer number (7158336).

Almost surely, 2^28409519 is an apocalyptic number.

28409519 is a deficient number, since it is larger than the sum of its proper divisors (223825).

28409519 is a wasteful number, since it uses less digits than its factorization.

28409519 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 223824.

The product of its (nonzero) digits is 25920, while the sum is 38.

The square root of 28409519 is about 5330.0580672259. The cubic root of 28409519 is about 305.1321437606.

The spelling of 28409519 in words is "twenty-eight million, four hundred nine thousand, five hundred nineteen".