28279717 has 2 divisors, whose sum is σ = 28279718. Its totient is φ = 28279716.

The previous prime is 28279679. The next prime is 28279747. The reversal of 28279717 is 71797282.

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., 22524516 + 5755201 = 4746^2 + 2399^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28279717 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28279747) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14139858 + 14139859.

It is an arithmetic number, because the mean of its divisors is an integer number (14139859).

Almost surely, 2^28279717 is an apocalyptic number.

It is an amenable number.

28279717 is a deficient number, since it is larger than the sum of its proper divisors (1).

28279717 is an equidigital number, since it uses as much as digits as its factorization.

28279717 is an evil number, because the sum of its binary digits is even.

The product of its digits is 98784, while the sum is 43.

The square root of 28279717 is about 5317.8677117807. The cubic root of 28279717 is about 304.6667218634. Note that the first 3 decimals are identical.

It can be divided in two parts, 2827 and 9717, that added together give a square (12544 = 112²).

The spelling of 28279717 in words is "twenty-eight million, two hundred seventy-nine thousand, seven hundred seventeen".