28663986 has 32 divisors (see below), whose sum is σ = 62112960. Its totient is φ = 8766144.

The previous prime is 28663939. The next prime is 28664071. The reversal of 28663986 is 68936682.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12936 + ... + 14988.

It is an arithmetic number, because the mean of its divisors is an integer number (1941030).

Almost surely, 2^28663986 is an apocalyptic number.

28663986 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

28663986 is an abundant number, since it is smaller than the sum of its proper divisors (33448974).

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

28663986 is a wasteful number, since it uses less digits than its factorization.

28663986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2250.

The product of its digits is 746496, while the sum is 48.

The square root of 28663986 is about 5353.8757923583. The cubic root of 28663986 is about 306.0404705326.

The spelling of 28663986 in words is "twenty-eight million, six hundred sixty-three thousand, nine hundred eighty-six".