28186986 has 16 divisors (see below), whose sum is σ = 59690304. Its totient is φ = 8842944.

The previous prime is 28186931. The next prime is 28186987. The reversal of 28186986 is 68968182.

It is not an unprimeable number, because it can be changed into a prime (28186987) 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 7 ways as a sum of consecutive naturals, for example, 138070 + ... + 138273.

It is an arithmetic number, because the mean of its divisors is an integer number (3730644).

Almost surely, 2^28186986 is an apocalyptic number.

28186986 is an abundant number, since it is smaller than the sum of its proper divisors (31503318).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28186986 is a wasteful number, since it uses less digits than its factorization.

28186986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 276365.

The product of its digits is 331776, while the sum is 48.

The square root of 28186986 is about 5309.1417385487. The cubic root of 28186986 is about 304.3333499953. Note that the first 4 decimals are identical.

The spelling of 28186986 in words is "twenty-eight million, one hundred eighty-six thousand, nine hundred eighty-six".