28007897 has 2 divisors, whose sum is σ = 28007898. Its totient is φ = 28007896.

The previous prime is 28007873. The next prime is 28007899. The reversal of 28007897 is 79870082.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21752896 + 6255001 = 4664^2 + 2501^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28007897 is a prime.

Together with 28007899, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28007899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14003948 + 14003949.

It is an arithmetic number, because the mean of its divisors is an integer number (14003949).

Almost surely, 2^28007897 is an apocalyptic number.

It is an amenable number.

28007897 is a deficient number, since it is larger than the sum of its proper divisors (1).

28007897 is an equidigital number, since it uses as much as digits as its factorization.

28007897 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 56448, while the sum is 41.

The square root of 28007897 is about 5292.2487658839. The cubic root of 28007897 is about 303.6874420555.

The spelling of 28007897 in words is "twenty-eight million, seven thousand, eight hundred ninety-seven".