28361009 has 4 divisors (see below), whose sum is σ = 28385280. Its totient is φ = 28336740.

The previous prime is 28360987. The next prime is 28361027. The reversal of 28361009 is 90016382.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28361009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28361309) 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, 10289 + ... + 12750.

It is an arithmetic number, because the mean of its divisors is an integer number (7096320).

Almost surely, 2^28361009 is an apocalyptic number.

It is an amenable number.

28361009 is a deficient number, since it is larger than the sum of its proper divisors (24271).

28361009 is a wasteful number, since it uses less digits than its factorization.

28361009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24270.

The product of its (nonzero) digits is 2592, while the sum is 29.

The square root of 28361009 is about 5325.5055159111. The cubic root of 28361009 is about 304.9583710988.

The spelling of 28361009 in words is "twenty-eight million, three hundred sixty-one thousand, nine".