26640 has 60 divisors (see below), whose sum is σ = 91884. Its totient is φ = 6912.

The previous prime is 26633. The next prime is 26641. The reversal of 26640 is 4662.

26640 is a `hidden beast` number, since 2 + 664 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 17424 + 9216 = 132^2 + 96^2 .

It is a tau number, because it is divible by the number of its divisors (60).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a plaindrome in base 14.

It is a zygodrome in base 3 and base 14.

It is not an unprimeable number, because it can be changed into a prime (26641) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 702 + ... + 738.

2²⁶⁶⁴⁰ is an apocalyptic number.

26640 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 26640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45942).

26640 is an abundant number, since it is smaller than the sum of its proper divisors (65244).

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

26640 is a wasteful number, since it uses less digits than its factorization.

26640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56 (or 47 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 26640 is about 163.2176461048. The cubic root of 26640 is about 29.8660696451.

It can be divided in two parts, 26 and 640, that added together give a palindrome (666).

The spelling of 26640 in words is "twenty-six thousand, six hundred forty".