12666780 has 120 divisors (see below), whose sum is σ = 45453408. Its totient is φ = 2892672.

The previous prime is 12666779. The next prime is 12666803. The reversal of 12666780 is 8766621.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

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 39 ways as a sum of consecutive naturals, for example, 10782 + ... + 11898.

Almost surely, 2^12666780 is an apocalyptic number.

12666780 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 12666780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22726704).

12666780 is an abundant number, since it is smaller than the sum of its proper divisors (32786628).

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

12666780 is a wasteful number, since it uses less digits than its factorization.

12666780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1145 (or 1134 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 12666780 is about 3559.0420059336. The cubic root of 12666780 is about 233.1070504668.

The spelling of 12666780 in words is "twelve million, six hundred sixty-six thousand, seven hundred eighty".