12780828 has 54 divisors (see below), whose sum is σ = 33616856. Its totient is φ = 4251528.

The previous prime is 12780827. The next prime is 12780869. The reversal of 12780828 is 82808721.

It is a tau number, because it is divible by the number of its divisors (54).

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

It is a zygodrome in base 3.

It is a junction number, because it is equal to n+sod(n) for n = 12780792 and 12780801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12780827) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 26001 + ... + 26487.

Almost surely, 2^12780828 is an apocalyptic number.

12780828 is a gapful number since it is divisible by the number (18) 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 12780828, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16808428).

12780828 is an abundant number, since it is smaller than the sum of its proper divisors (20836028).

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

12780828 is an frugal number, since it uses more digits than its factorization.

12780828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 515 (or 492 counting only the distinct ones).

The product of its (nonzero) digits is 14336, while the sum is 36.

The square root of 12780828 is about 3575.0283914957. The cubic root of 12780828 is about 233.8045705567.

The spelling of 12780828 in words is "twelve million, seven hundred eighty thousand, eight hundred twenty-eight".