6687944 has 8 divisors (see below), whose sum is σ = 12539910. Its totient is φ = 3343968.

The previous prime is 6687931. The next prime is 6687973. The reversal of 6687944 is 4497866.

It can be written as a sum of positive squares in only one way, i.e., 5808100 + 879844 = 2410^2 + 938^2 .

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

It is a d-powerful number, because it can be written as 6² + 6² + 8⁵ + 7⁷ + 9⁷ + 4² + 4¹⁰ .

It is a junction number, because it is equal to n+sod(n) for n = 6687895 and 6687904.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 417989 + ... + 418004.

Almost surely, 2^6687944 is an apocalyptic number.

It is an amenable number.

6687944 is a deficient number, since it is larger than the sum of its proper divisors (5851966).

6687944 is a wasteful number, since it uses less digits than its factorization.

6687944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 835999 (or 835995 counting only the distinct ones).

The product of its digits is 290304, while the sum is 44.

The square root of 6687944 is about 2586.1059529725. The cubic root of 6687944 is about 188.4072205105.

The spelling of 6687944 in words is "six million, six hundred eighty-seven thousand, nine hundred forty-four".