6678639 has 32 divisors (see below), whose sum is σ = 10944000. Its totient is φ = 3991680.

The previous prime is 6678629. The next prime is 6678641. The reversal of 6678639 is 9368766.

6678639 is a `hidden beast` number, since 6 + 6 + 7 + 8 + 639 = 666.

It is not a de Polignac number, because 6678639 - 2⁸ = 6678383 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 6678594 and 6678603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6678629) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 33462 + ... + 33660.

It is an arithmetic number, because the mean of its divisors is an integer number (342000).

Almost surely, 2^6678639 is an apocalyptic number.

6678639 is a deficient number, since it is larger than the sum of its proper divisors (4265361).

6678639 is a wasteful number, since it uses less digits than its factorization.

6678639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 332 (or 326 counting only the distinct ones).

The product of its digits is 326592, while the sum is 45.

The square root of 6678639 is about 2584.3062898968. The cubic root of 6678639 is about 188.3198023710.

The spelling of 6678639 in words is "six million, six hundred seventy-eight thousand, six hundred thirty-nine".