12840342 has 8 divisors (see below), whose sum is σ = 25680696. Its totient is φ = 4280112.

The previous prime is 12840337. The next prime is 12840343. The reversal of 12840342 is 24304821.

It is a sphenic number, since it is the product of 3 distinct primes.

12840342 is an admirable number.

It is a Smith number, since the sum of its digits (24) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12840343) 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, 1070023 + ... + 1070034.

It is an arithmetic number, because the mean of its divisors is an integer number (3210087).

Almost surely, 2^12840342 is an apocalyptic number.

12840342 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12840342 is a wasteful number, since it uses less digits than its factorization.

12840342 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2140062.

The product of its (nonzero) digits is 1536, while the sum is 24.

The square root of 12840342 is about 3583.3422945624. The cubic root of 12840342 is about 234.1669128358.

It can be divided in two parts, 128 and 40342, that added together give a triangular number (40470 = T₂₈₄).

The spelling of 12840342 in words is "twelve million, eight hundred forty thousand, three hundred forty-two".