28502009 has 2 divisors, whose sum is σ = 28502010. Its totient is φ = 28502008.

The previous prime is 28501999. The next prime is 28502029. The reversal of 28502009 is 90020582.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19669225 + 8832784 = 4435^2 + 2972^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28502009 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28502029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14251004 + 14251005.

It is an arithmetic number, because the mean of its divisors is an integer number (14251005).

Almost surely, 2^28502009 is an apocalyptic number.

It is an amenable number.

28502009 is a deficient number, since it is larger than the sum of its proper divisors (1).

28502009 is an equidigital number, since it uses as much as digits as its factorization.

28502009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 28502009 is about 5338.7272827894. The cubic root of 28502009 is about 305.4629143625.

The spelling of 28502009 in words is "twenty-eight million, five hundred two thousand, nine".