12781278 has 48 divisors (see below), whose sum is σ = 28675296. Its totient is φ = 4112640.

The previous prime is 12781271. The next prime is 12781291. The reversal of 12781278 is 87218721.

It is a happy number.

12781278 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×12781278² = 326722134626568, which contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12781271) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 93226 + ... + 93362.

It is an arithmetic number, because the mean of its divisors is an integer number (597402).

Almost surely, 2^12781278 is an apocalyptic number.

12781278 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

12781278 is an abundant number, since it is smaller than the sum of its proper divisors (15894018).

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

12781278 is a wasteful number, since it uses less digits than its factorization.

12781278 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 289 (or 286 counting only the distinct ones).

The product of its digits is 12544, while the sum is 36.

The square root of 12781278 is about 3575.0913275048. The cubic root of 12781278 is about 233.8073145318.

Adding to 12781278 its reverse (87218721), we get a palindrome (99999999).

It can be divided in two parts, 1278 and 1278, that added together give a triangular number (2556 = T₇₁).

The spelling of 12781278 in words is "twelve million, seven hundred eighty-one thousand, two hundred seventy-eight".