28585217 has 2 divisors, whose sum is σ = 28585218. Its totient is φ = 28585216.

The previous prime is 28585189. The next prime is 28585231. The reversal of 28585217 is 71258582.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23902321 + 4682896 = 4889^2 + 2164^2 .

It is a cyclic number.

It is not a de Polignac number, because 28585217 - 2⁸ = 28584961 is a prime.

It is a super-2 number, since 2×28585217² = 1634229261874178, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28585237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14292608 + 14292609.

It is an arithmetic number, because the mean of its divisors is an integer number (14292609).

Almost surely, 2^28585217 is an apocalyptic number.

It is an amenable number.

28585217 is a deficient number, since it is larger than the sum of its proper divisors (1).

28585217 is an equidigital number, since it uses as much as digits as its factorization.

28585217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 44800, while the sum is 38.

The square root of 28585217 is about 5346.5144720650. The cubic root of 28585217 is about 305.7598789771.

The spelling of 28585217 in words is "twenty-eight million, five hundred eighty-five thousand, two hundred seventeen".