12639944 has 8 divisors (see below), whose sum is σ = 23699910. Its totient is φ = 6319968.

The previous prime is 12639943. The next prime is 12639947. The reversal of 12639944 is 44993621.

It can be written as a sum of positive squares in only one way, i.e., 12517444 + 122500 = 3538^2 + 350^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 12639898 and 12639907.

It is not an unprimeable number, because it can be changed into a prime (12639941) 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, 789989 + ... + 790004.

Almost surely, 2^12639944 is an apocalyptic number.

It is an amenable number.

12639944 is a deficient number, since it is larger than the sum of its proper divisors (11059966).

12639944 is a wasteful number, since it uses less digits than its factorization.

12639944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1579999 (or 1579995 counting only the distinct ones).

The product of its digits is 46656, while the sum is 38.

The square root of 12639944 is about 3555.2698913022. The cubic root of 12639944 is about 232.9423128937.

The spelling of 12639944 in words is "twelve million, six hundred thirty-nine thousand, nine hundred forty-four".