28009829 has 8 divisors (see below), whose sum is σ = 29703960. Its totient is φ = 26320896.

The previous prime is 28009823. The next prime is 28009831. The reversal of 28009829 is 92890082.

It can be written as a sum of positive squares in 4 ways, for example, as 4950625 + 23059204 = 2225^2 + 4802^2 .

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

It is a de Polignac number, because none of the positive numbers 2^k-28009829 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 28009792 and 28009801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28009823) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18887 + ... + 20315.

It is an arithmetic number, because the mean of its divisors is an integer number (3712995).

Almost surely, 2^28009829 is an apocalyptic number.

It is an amenable number.

28009829 is a deficient number, since it is larger than the sum of its proper divisors (1694131).

28009829 is a wasteful number, since it uses less digits than its factorization.

28009829 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2599.

The product of its (nonzero) digits is 20736, while the sum is 38.

The square root of 28009829 is about 5292.4312938384. The cubic root of 28009829 is about 303.6944247367.

The spelling of 28009829 in words is "twenty-eight million, nine thousand, eight hundred twenty-nine".