27840820 has 36 divisors (see below), whose sum is σ = 68013540. Its totient is φ = 9545088.

The previous prime is 27840811. The next prime is 27840863. The reversal of 27840820 is 2804872.

It can be written as a sum of positive squares in 2 ways, for example, as 13972644 + 13868176 = 3738^2 + 3724^2 .

It is a super-2 number, since 2×27840820² = 1550222516544800, which contains 22 as substring.

It is a congruent number.

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 11 ways as a sum of consecutive naturals, for example, 13225 + ... + 15184.

It is an arithmetic number, because the mean of its divisors is an integer number (1889265).

Almost surely, 2^27840820 is an apocalyptic number.

27840820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

27840820 is an abundant number, since it is smaller than the sum of its proper divisors (40172720).

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

27840820 is a wasteful number, since it uses less digits than its factorization.

27840820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28432 (or 28423 counting only the distinct ones).

The product of its (nonzero) digits is 7168, while the sum is 31.

The square root of 27840820 is about 5276.4400877865. The cubic root of 27840820 is about 303.0823696736.

The spelling of 27840820 in words is "twenty-seven million, eight hundred forty thousand, eight hundred twenty".