12806640 has 360 divisors, whose sum is σ = 56402640. Its totient is φ = 2661120.

The previous prime is 12806621. The next prime is 12806641. The reversal of 12806640 is 4660821.

12806640 is a `hidden beast` number, since 12 + 8 + 0 + 6 + 640 = 666.

12806640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (360).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12806641) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1164235 + ... + 1164245.

It is an arithmetic number, because the mean of its divisors is an integer number (156674).

Almost surely, 2^12806640 is an apocalyptic number.

12806640 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 12806640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28201320).

12806640 is an abundant number, since it is smaller than the sum of its proper divisors (43596000).

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

12806640 is a wasteful number, since it uses less digits than its factorization.

12806640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58 (or 28 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 12806640 is about 3578.6366118957. The cubic root of 12806640 is about 233.9618609768.

The spelling of 12806640 in words is "twelve million, eight hundred six thousand, six hundred forty".