12665680 has 80 divisors (see below), whose sum is σ = 31872960. Its totient is φ = 4663296.

The previous prime is 12665677. The next prime is 12665687. The reversal of 12665680 is 8656621.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12665687) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 91051 + ... + 91189.

It is an arithmetic number, because the mean of its divisors is an integer number (398412).

Almost surely, 2^12665680 is an apocalyptic number.

12665680 is a gapful number since it is divisible by the number (10) 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 12665680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15936480).

12665680 is an abundant number, since it is smaller than the sum of its proper divisors (19207280).

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

12665680 is a wasteful number, since it uses less digits than its factorization.

With its predecessor (12665679) it forms an eRAP, since the sums of their prime factors are consecutive (235 and 236).

12665680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 236 (or 230 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 34.

The square root of 12665680 is about 3558.8874666109. The cubic root of 12665680 is about 233.1003024961.

It can be divided in two parts, 126656 and 80, that added together give a square (126736 = 356²).

The spelling of 12665680 in words is "twelve million, six hundred sixty-five thousand, six hundred eighty".