27988820 has 12 divisors (see below), whose sum is σ = 58776564. Its totient is φ = 11195520.

The previous prime is 27988811. The next prime is 27988837. The reversal of 27988820 is 2888972.

It can be written as a sum of positive squares in 2 ways, for example, as 12716356 + 15272464 = 3566^2 + 3908^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 699701 + ... + 699740.

It is an arithmetic number, because the mean of its divisors is an integer number (4898047).

Almost surely, 2^27988820 is an apocalyptic number.

27988820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

27988820 is an abundant number, since it is smaller than the sum of its proper divisors (30787744).

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

27988820 is a wasteful number, since it uses less digits than its factorization.

27988820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1399450 (or 1399448 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 44.

The square root of 27988820 is about 5290.4461059536. The cubic root of 27988820 is about 303.6184762540.

The spelling of 27988820 in words is "twenty-seven million, nine hundred eighty-eight thousand, eight hundred twenty".