28188697 has 2 divisors, whose sum is σ = 28188698. Its totient is φ = 28188696.

The previous prime is 28188691. The next prime is 28188757. The reversal of 28188697 is 79688182.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26998416 + 1190281 = 5196^2 + 1091^2 .

It is a cyclic number.

It is not a de Polignac number, because 28188697 - 2⁷ = 28188569 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28188697.

It is not a weakly prime, because it can be changed into another prime (28188691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14094348 + 14094349.

It is an arithmetic number, because the mean of its divisors is an integer number (14094349).

Almost surely, 2^28188697 is an apocalyptic number.

It is an amenable number.

28188697 is a deficient number, since it is larger than the sum of its proper divisors (1).

28188697 is an equidigital number, since it uses as much as digits as its factorization.

28188697 is an evil number, because the sum of its binary digits is even.

The product of its digits is 387072, while the sum is 49.

The square root of 28188697 is about 5309.3028732594. The cubic root of 28188697 is about 304.3395077286.

The spelling of 28188697 in words is "twenty-eight million, one hundred eighty-eight thousand, six hundred ninety-seven".