12781942 has 4 divisors (see below), whose sum is σ = 19172916. Its totient is φ = 6390970.

The previous prime is 12781939. The next prime is 12782009. The reversal of 12781942 is 24918721.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24918721 = 271 ⋅91951.

It is a junction number, because it is equal to n+sod(n) for n = 12781898 and 12781907.

It is a congruent number.

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 as a sum of consecutive naturals, namely, 3195484 + ... + 3195487.

It is an arithmetic number, because the mean of its divisors is an integer number (4793229).

Almost surely, 2^12781942 is an apocalyptic number.

12781942 is a deficient number, since it is larger than the sum of its proper divisors (6390974).

12781942 is an equidigital number, since it uses as much as digits as its factorization.

12781942 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6390973.

The product of its digits is 8064, while the sum is 34.

The square root of 12781942 is about 3575.1841910593. The cubic root of 12781942 is about 233.8113633019.

The spelling of 12781942 in words is "twelve million, seven hundred eighty-one thousand, nine hundred forty-two".