12840644 has 12 divisors (see below), whose sum is σ = 23793084. Its totient is φ = 6042624.

The previous prime is 12840643. The next prime is 12840677. The reversal of 12840644 is 44604821.

It can be written as a sum of positive squares in 2 ways, for example, as 11303044 + 1537600 = 3362^2 + 1240^2 .

It is not an unprimeable number, because it can be changed into a prime (12840643) 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, 94349 + ... + 94484.

It is an arithmetic number, because the mean of its divisors is an integer number (1982757).

Almost surely, 2^12840644 is an apocalyptic number.

It is an amenable number.

12840644 is a deficient number, since it is larger than the sum of its proper divisors (10952440).

12840644 is a wasteful number, since it uses less digits than its factorization.

12840644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 188854 (or 188852 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 29.

The square root of 12840644 is about 3583.3844337442. The cubic root of 12840644 is about 234.1687486605.

The spelling of 12840644 in words is "twelve million, eight hundred forty thousand, six hundred forty-four".