12840426 has 12 divisors (see below), whose sum is σ = 27820962. Its totient is φ = 4280136.

The previous prime is 12840391. The next prime is 12840427. The reversal of 12840426 is 62404821.

It can be written as a sum of positive squares in only one way, i.e., 12595401 + 245025 = 3549^2 + 495^2 .

It is a super-2 number, since 2×12840426² = 329753079722952, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 12840426.

It is not an unprimeable number, because it can be changed into a prime (12840427) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 356661 + ... + 356696.

Almost surely, 2^12840426 is an apocalyptic number.

12840426 is an abundant number, since it is smaller than the sum of its proper divisors (14980536).

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

12840426 is a wasteful number, since it uses less digits than its factorization.

12840426 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 713365 (or 713362 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

The square root of 12840426 is about 3583.3540154442. The cubic root of 12840426 is about 234.1674234654.

The spelling of 12840426 in words is "twelve million, eight hundred forty thousand, four hundred twenty-six".