12806820 has 108 divisors (see below), whose sum is σ = 42165396. Its totient is φ = 3144960.

The previous prime is 12806749. The next prime is 12806861. The reversal of 12806820 is 2860821.

It can be written as a sum of positive squares in 6 ways, for example, as 6843456 + 5963364 = 2616^2 + 2442^2 .

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 35 ways as a sum of consecutive naturals, for example, 30210 + ... + 30630.

Almost surely, 2^12806820 is an apocalyptic number.

12806820 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 12806820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21082698).

12806820 is an abundant number, since it is smaller than the sum of its proper divisors (29358576).

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

12806820 is a wasteful number, since it uses less digits than its factorization.

12806820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 462 (or 444 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 12806820 is about 3578.6617610498. The cubic root of 12806820 is about 233.9629570993.

It can be divided in two parts, 1280 and 6820, that added together give a square (8100 = 90²).

The spelling of 12806820 in words is "twelve million, eight hundred six thousand, eight hundred twenty".