28974809 has 4 divisors (see below), whose sum is σ = 28990116. Its totient is φ = 28959504.

The previous prime is 28974793. The next prime is 28974833. The reversal of 28974809 is 90847982.

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 27825625 + 1149184 = 5275^2 + 1072^2 .

It is a cyclic number.

It is not a de Polignac number, because 28974809 - 2⁴ = 28974793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28974859) 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, 4334 + ... + 8759.

It is an arithmetic number, because the mean of its divisors is an integer number (7247529).

Almost surely, 2^28974809 is an apocalyptic number.

It is an amenable number.

28974809 is a deficient number, since it is larger than the sum of its proper divisors (15307).

28974809 is a wasteful number, since it uses less digits than its factorization.

28974809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15306.

The product of its (nonzero) digits is 290304, while the sum is 47.

The square root of 28974809 is about 5382.8253733518. The cubic root of 28974809 is about 307.1426973344.

The spelling of 28974809 in words is "twenty-eight million, nine hundred seventy-four thousand, eight hundred nine".