28509434 has 8 divisors (see below), whose sum is σ = 42786900. Its totient is φ = 14247136.

The previous prime is 28509431. The next prime is 28509457. The reversal of 28509434 is 43490582.

It can be written as a sum of positive squares in 2 ways, for example, as 27008809 + 1500625 = 5197^2 + 1225^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 28509394 and 28509403.

It is not an unprimeable number, because it can be changed into a prime (28509431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4832 + ... + 8964.

Almost surely, 2^28509434 is an apocalyptic number.

28509434 is a deficient number, since it is larger than the sum of its proper divisors (14277466).

28509434 is a wasteful number, since it uses less digits than its factorization.

28509434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7584.

The product of its (nonzero) digits is 34560, while the sum is 35.

The square root of 28509434 is about 5339.4226279627. The cubic root of 28509434 is about 305.4894372323.

The spelling of 28509434 in words is "twenty-eight million, five hundred nine thousand, four hundred thirty-four".