6681394 has 4 divisors (see below), whose sum is σ = 10022094. Its totient is φ = 3340696.

The previous prime is 6681377. The next prime is 6681403. The reversal of 6681394 is 4931866.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 4931866 = 2 ⋅2465933.

It can be written as a sum of positive squares in only one way, i.e., 6436369 + 245025 = 2537^2 + 495^2 .

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 1670347 + ... + 1670350.

Almost surely, 2^6681394 is an apocalyptic number.

6681394 is a deficient number, since it is larger than the sum of its proper divisors (3340700).

6681394 is a wasteful number, since it uses less digits than its factorization.

6681394 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3340699.

The product of its digits is 31104, while the sum is 37.

The square root of 6681394 is about 2584.8392599928. The cubic root of 6681394 is about 188.3456933613.

The spelling of 6681394 in words is "six million, six hundred eighty-one thousand, three hundred ninety-four".