28670909 has 2 divisors, whose sum is σ = 28670910. Its totient is φ = 28670908.

The previous prime is 28670899. The next prime is 28670911. The reversal of 28670909 is 90907682.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25351225 + 3319684 = 5035^2 + 1822^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28670909 is a prime.

Together with 28670911, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28670989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14335454 + 14335455.

It is an arithmetic number, because the mean of its divisors is an integer number (14335455).

Almost surely, 2^28670909 is an apocalyptic number.

It is an amenable number.

28670909 is a deficient number, since it is larger than the sum of its proper divisors (1).

28670909 is an equidigital number, since it uses as much as digits as its factorization.

28670909 is an evil number, because the sum of its binary digits is even.

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

The square root of 28670909 is about 5354.5222942855. The cubic root of 28670909 is about 306.0651071112.

The spelling of 28670909 in words is "twenty-eight million, six hundred seventy thousand, nine hundred nine".