28086397 has 4 divisors (see below), whose sum is σ = 29738556. Its totient is φ = 26434240.

The previous prime is 28086391. The next prime is 28086433. The reversal of 28086397 is 79368082.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 17255716 + 10830681 = 4154^2 + 3291^2 .

It is a cyclic number.

It is not a de Polignac number, because 28086397 - 2¹¹ = 28084349 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28086391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 826054 + ... + 826087.

It is an arithmetic number, because the mean of its divisors is an integer number (7434639).

Almost surely, 2^28086397 is an apocalyptic number.

It is an amenable number.

28086397 is a deficient number, since it is larger than the sum of its proper divisors (1652159).

28086397 is a wasteful number, since it uses less digits than its factorization.

28086397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1652158.

The product of its (nonzero) digits is 145152, while the sum is 43.

The square root of 28086397 is about 5299.6600834393. The cubic root of 28086397 is about 303.9709005214.

The spelling of 28086397 in words is "twenty-eight million, eighty-six thousand, three hundred ninety-seven".