28266191 has 2 divisors, whose sum is σ = 28266192. Its totient is φ = 28266190.

The previous prime is 28266137. The next prime is 28266197. The reversal of 28266191 is 19166282.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28266191 - 2⁶ = 28266127 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28266197) 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, 14133095 + 14133096.

It is an arithmetic number, because the mean of its divisors is an integer number (14133096).

Almost surely, 2^28266191 is an apocalyptic number.

28266191 is a deficient number, since it is larger than the sum of its proper divisors (1).

28266191 is an equidigital number, since it uses as much as digits as its factorization.

28266191 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10368, while the sum is 35.

The square root of 28266191 is about 5316.5958093502. The cubic root of 28266191 is about 304.6181407636.

Subtracting from 28266191 its reverse (19166282), we obtain a palindrome (9099909).

The spelling of 28266191 in words is "twenty-eight million, two hundred sixty-six thousand, one hundred ninety-one".