28790609 has 4 divisors (see below), whose sum is σ = 28809060. Its totient is φ = 28772160.

The previous prime is 28790579. The next prime is 28790611. The reversal of 28790609 is 90609782.

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 20070400 + 8720209 = 4480^2 + 2953^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28790609 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28790659) 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, 6644 + ... + 10085.

It is an arithmetic number, because the mean of its divisors is an integer number (7202265).

Almost surely, 2^28790609 is an apocalyptic number.

It is an amenable number.

28790609 is a deficient number, since it is larger than the sum of its proper divisors (18451).

28790609 is a wasteful number, since it uses less digits than its factorization.

28790609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18450.

The product of its (nonzero) digits is 54432, while the sum is 41.

The square root of 28790609 is about 5365.6881198966. The cubic root of 28790609 is about 306.4904526138.

The spelling of 28790609 in words is "twenty-eight million, seven hundred ninety thousand, six hundred nine".