28718717 has 2 divisors, whose sum is σ = 28718718. Its totient is φ = 28718716.

The previous prime is 28718713. The next prime is 28718731. The reversal of 28718717 is 71781782.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 22905796 + 5812921 = 4786^2 + 2411^2 .

It is a cyclic number.

It is not a de Polignac number, because 28718717 - 2² = 28718713 is a prime.

It is a super-2 number, since 2×28718717² = 1649529412252178, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28718713) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14359358 + 14359359.

It is an arithmetic number, because the mean of its divisors is an integer number (14359359).

Almost surely, 2^28718717 is an apocalyptic number.

It is an amenable number.

28718717 is a deficient number, since it is larger than the sum of its proper divisors (1).

28718717 is an equidigital number, since it uses as much as digits as its factorization.

28718717 is an evil number, because the sum of its binary digits is even.

The product of its digits is 43904, while the sum is 41.

The square root of 28718717 is about 5358.9846986160. The cubic root of 28718717 is about 306.2351311954.

The spelling of 28718717 in words is "twenty-eight million, seven hundred eighteen thousand, seven hundred seventeen".