28207717 has 2 divisors, whose sum is σ = 28207718. Its totient is φ = 28207716.

The previous prime is 28207693. The next prime is 28207721. The reversal of 28207717 is 71770282.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21520321 + 6687396 = 4639^2 + 2586^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28207717 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28207747) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14103858 + 14103859.

It is an arithmetic number, because the mean of its divisors is an integer number (14103859).

Almost surely, 2^28207717 is an apocalyptic number.

It is an amenable number.

28207717 is a deficient number, since it is larger than the sum of its proper divisors (1).

28207717 is an equidigital number, since it uses as much as digits as its factorization.

28207717 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10976, while the sum is 34.

The square root of 28207717 is about 5311.0937668243. The cubic root of 28207717 is about 304.4079422032.

Adding to 28207717 its reverse (71770282), we get a palindrome (99977999).

The spelling of 28207717 in words is "twenty-eight million, two hundred seven thousand, seven hundred seventeen".