12857842 has 4 divisors (see below), whose sum is σ = 19286766. Its totient is φ = 6428920.

The previous prime is 12857827. The next prime is 12857843. The reversal of 12857842 is 24875821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24875821 = 733 ⋅33937.

It can be written as a sum of positive squares in only one way, i.e., 12187081 + 670761 = 3491^2 + 819^2 .

It is not an unprimeable number, because it can be changed into a prime (12857843) by changing a digit.

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, 3214459 + ... + 3214462.

Almost surely, 2^12857842 is an apocalyptic number.

12857842 is a deficient number, since it is larger than the sum of its proper divisors (6428924).

12857842 is an equidigital number, since it uses as much as digits as its factorization.

12857842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6428923.

The product of its digits is 35840, while the sum is 37.

The square root of 12857842 is about 3585.7833174915. The cubic root of 12857842 is about 234.2732459513.

It can be divided in two parts, 128 and 57842, that added together give a triangular number (57970 = T₃₄₀).

The spelling of 12857842 in words is "twelve million, eight hundred fifty-seven thousand, eight hundred forty-two".