12781231 has 4 divisors (see below), whose sum is σ = 12898600. Its totient is φ = 12663864.

The previous prime is 12781193. The next prime is 12781267. The reversal of 12781231 is 13218721.

It is a happy number.

12781231 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13218721 = 23 ⋅574727.

It is a cyclic number.

It is not a de Polignac number, because 12781231 - 2⁷ = 12781103 is a prime.

It is a super-2 number, since 2×12781231² = 326719731750722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12781196 and 12781205.

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 3 ways as a sum of consecutive naturals, for example, 58521 + ... + 58738.

It is an arithmetic number, because the mean of its divisors is an integer number (3224650).

Almost surely, 2^12781231 is an apocalyptic number.

12781231 is a deficient number, since it is larger than the sum of its proper divisors (117369).

12781231 is a wasteful number, since it uses less digits than its factorization.

12781231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117368.

The product of its digits is 672, while the sum is 25.

The square root of 12781231 is about 3575.0847542401. The cubic root of 12781231 is about 233.8070279419.

Adding to 12781231 its reverse (13218721), we get a palindrome (25999952).

The spelling of 12781231 in words is "twelve million, seven hundred eighty-one thousand, two hundred thirty-one".