12781945 has 16 divisors (see below), whose sum is σ = 16809408. Its totient is φ = 9253440.

The previous prime is 12781939. The next prime is 12782009. The reversal of 12781945 is 54918721.

It is not a de Polignac number, because 12781945 - 2⁷ = 12781817 is a prime.

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 15 ways as a sum of consecutive naturals, for example, 16507 + ... + 17263.

It is an arithmetic number, because the mean of its divisors is an integer number (1050588).

Almost surely, 2^12781945 is an apocalyptic number.

It is an amenable number.

12781945 is a deficient number, since it is larger than the sum of its proper divisors (4027463).

12781945 is a wasteful number, since it uses less digits than its factorization.

12781945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1080.

The product of its digits is 20160, while the sum is 37.

The square root of 12781945 is about 3575.1846106180. The cubic root of 12781945 is about 233.8113815943.

It can be divided in two parts, 1278 and 1945, that added together give a palindrome (3223).

The spelling of 12781945 in words is "twelve million, seven hundred eighty-one thousand, nine hundred forty-five".