28170917 has 2 divisors, whose sum is σ = 28170918. Its totient is φ = 28170916.

The previous prime is 28170913. The next prime is 28170937. The reversal of 28170917 is 71907182.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27394756 + 776161 = 5234^2 + 881^2 .

It is a cyclic number.

It is not a de Polignac number, because 28170917 - 2² = 28170913 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28170913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14085458 + 14085459.

It is an arithmetic number, because the mean of its divisors is an integer number (14085459).

Almost surely, 2^28170917 is an apocalyptic number.

It is an amenable number.

28170917 is a deficient number, since it is larger than the sum of its proper divisors (1).

28170917 is an equidigital number, since it uses as much as digits as its factorization.

28170917 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7056, while the sum is 35.

The square root of 28170917 is about 5307.6281896908. The cubic root of 28170917 is about 304.2755069633.

The spelling of 28170917 in words is "twenty-eight million, one hundred seventy thousand, nine hundred seventeen".