12840071 has 4 divisors (see below), whose sum is σ = 13113312. Its totient is φ = 12566832.

The previous prime is 12840031. The next prime is 12840089. The reversal of 12840071 is 17004821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17004821 = 179 ⋅94999.

It is a cyclic number.

It is not a de Polignac number, because 12840071 - 2⁶ = 12840007 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12840001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 136550 + ... + 136643.

It is an arithmetic number, because the mean of its divisors is an integer number (3278328).

Almost surely, 2^12840071 is an apocalyptic number.

12840071 is a deficient number, since it is larger than the sum of its proper divisors (273241).

12840071 is an equidigital number, since it uses as much as digits as its factorization.

12840071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 273240.

The product of its (nonzero) digits is 448, while the sum is 23.

The square root of 12840071 is about 3583.3044805040. The cubic root of 12840071 is about 234.1652654321.

Adding to 12840071 its reverse (17004821), we get a palindrome (29844892).

The spelling of 12840071 in words is "twelve million, eight hundred forty thousand, seventy-one".