27690 has 32 divisors (see below), whose sum is σ = 72576. Its totient is φ = 6720.

The previous prime is 27689. The next prime is 27691. The reversal of 27690 is 9672.

27690 = 40² + 41² + ... + 52².

It is an interprime number because it is at equal distance from previous prime (27689) and next prime (27691).

It is a super-2 number, since 2×27690² = 1533472200, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is a Curzon number.

It is a nialpdrome in base 6 and base 15.

It is a self number, because there is not a number n which added to its sum of digits gives 27690.

It is not an unprimeable number, because it can be changed into a prime (27691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 355 + ... + 425.

It is an arithmetic number, because the mean of its divisors is an integer number (2268).

2²⁷⁶⁹⁰ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 27690, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36288).

27690 is an abundant number, since it is smaller than the sum of its proper divisors (44886).

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

27690 is a wasteful number, since it uses less digits than its factorization.

27690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94.

The product of its (nonzero) digits is 756, while the sum is 24.

The square root of 27690 is about 166.4031249707. The cubic root of 27690 is about 30.2534089913.

It can be divided in two parts, 27 and 690, that added together give a palindrome (717).

The spelling of 27690 in words is "twenty-seven thousand, six hundred ninety".