28626209 has 2 divisors, whose sum is σ = 28626210. Its totient is φ = 28626208.

The previous prime is 28626193. The next prime is 28626239. The reversal of 28626209 is 90262682.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26214400 + 2411809 = 5120^2 + 1553^2 .

It is a cyclic number.

It is not a de Polignac number, because 28626209 - 2⁴ = 28626193 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28626239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14313104 + 14313105.

It is an arithmetic number, because the mean of its divisors is an integer number (14313105).

Almost surely, 2^28626209 is an apocalyptic number.

It is an amenable number.

28626209 is a deficient number, since it is larger than the sum of its proper divisors (1).

28626209 is an equidigital number, since it uses as much as digits as its factorization.

28626209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20736, while the sum is 35.

The square root of 28626209 is about 5350.3466242852. The cubic root of 28626209 is about 305.9059652391.

The spelling of 28626209 in words is "twenty-eight million, six hundred twenty-six thousand, two hundred nine".