28391227 has 2 divisors, whose sum is σ = 28391228. Its totient is φ = 28391226.

The previous prime is 28391197. The next prime is 28391249. The reversal of 28391227 is 72219382.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28391227 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 28391192 and 28391201.

It is not a weakly prime, because it can be changed into another prime (28391287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14195613 + 14195614.

It is an arithmetic number, because the mean of its divisors is an integer number (14195614).

Almost surely, 2^28391227 is an apocalyptic number.

28391227 is a deficient number, since it is larger than the sum of its proper divisors (1).

28391227 is an equidigital number, since it uses as much as digits as its factorization.

28391227 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12096, while the sum is 34.

The square root of 28391227 is about 5328.3418621556. The cubic root of 28391227 is about 305.0666413549.

The spelling of 28391227 in words is "twenty-eight million, three hundred ninety-one thousand, two hundred twenty-seven".