28651986 has 48 divisors (see below), whose sum is σ = 69571008. Its totient is φ = 8445600.

The previous prime is 28651969. The next prime is 28651991. The reversal of 28651986 is 68915682.

It is a Curzon number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 5371 + ... + 9281.

It is an arithmetic number, because the mean of its divisors is an integer number (1449396).

Almost surely, 2^28651986 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28651986, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34785504).

28651986 is an abundant number, since it is smaller than the sum of its proper divisors (40919022).

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

28651986 is a wasteful number, since it uses less digits than its factorization.

28651986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3967 (or 3964 counting only the distinct ones).

The product of its digits is 207360, while the sum is 45.

The square root of 28651986 is about 5352.7549915908. The cubic root of 28651986 is about 305.9977572564.

It can be divided in two parts, 2865 and 1986, that added together give a triangular number (4851 = T₉₈).

The spelling of 28651986 in words is "twenty-eight million, six hundred fifty-one thousand, nine hundred eighty-six".