12781836 has 72 divisors (see below), whose sum is σ = 34594560. Its totient is φ = 3969504.

The previous prime is 12781823. The next prime is 12781843. The reversal of 12781836 is 63818721.

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

It is an alternating number because its digits alternate between odd and even.

It is a self number, because there is not a number n which added to its sum of digits gives 12781836.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 35425 + ... + 35783.

It is an arithmetic number, because the mean of its divisors is an integer number (480480).

Almost surely, 2^12781836 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12781836, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17297280).

12781836 is an abundant number, since it is smaller than the sum of its proper divisors (21812724).

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

12781836 is a wasteful number, since it uses less digits than its factorization.

12781836 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 435 (or 430 counting only the distinct ones).

The product of its digits is 16128, while the sum is 36.

The square root of 12781836 is about 3575.1693666175. The cubic root of 12781836 is about 233.8107169715.

The spelling of 12781836 in words is "twelve million, seven hundred eighty-one thousand, eight hundred thirty-six".