27986820 has 48 divisors (see below), whose sum is σ = 78888768. Its totient is φ = 7413120.

The previous prime is 27986807. The next prime is 27986857. The reversal of 27986820 is 2868972.

It is a happy number.

It is a hoax number, since the sum of its digits (42) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7935 + ... + 10905.

It is an arithmetic number, because the mean of its divisors is an integer number (1643516).

Almost surely, 2^27986820 is an apocalyptic number.

27986820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 27986820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39444384).

27986820 is an abundant number, since it is smaller than the sum of its proper divisors (50901948).

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

27986820 is a wasteful number, since it uses less digits than its factorization.

27986820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3140 (or 3138 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 42.

The square root of 27986820 is about 5290.2570826001. The cubic root of 27986820 is about 303.6112441828.

The spelling of 27986820 in words is "twenty-seven million, nine hundred eighty-six thousand, eight hundred twenty".