27810640 has 180 divisors, whose sum is σ = 81486972. Its totient is φ = 8785920.

The previous prime is 27810613. The next prime is 27810649. The reversal of 27810640 is 4601872.

It can be written as a sum of positive squares in 6 ways, for example, as 2650384 + 25160256 = 1628^2 + 5016^2 .

It is a junction number, because it is equal to n+sod(n) for n = 27810599 and 27810608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27810649) by changing a digit.

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 35 ways as a sum of consecutive naturals, for example, 1635912 + ... + 1635928.

Almost surely, 2^27810640 is an apocalyptic number.

27810640 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 27810640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40743486).

27810640 is an abundant number, since it is smaller than the sum of its proper divisors (53676332).

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

27810640 is a wasteful number, since it uses less digits than its factorization.

27810640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78 (or 48 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 28.

The square root of 27810640 is about 5273.5794295715. The cubic root of 27810640 is about 302.9728143145.

The spelling of 27810640 in words is "twenty-seven million, eight hundred ten thousand, six hundred forty".