6658639 has 8 divisors (see below), whose sum is σ = 7196112. Its totient is φ = 6124800.

The previous prime is 6658637. The next prime is 6658649. The reversal of 6658639 is 9368566.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 6658639 - 2¹ = 6658637 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6658595 and 6658604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6658637) 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 7 ways as a sum of consecutive naturals, for example, 3864 + ... + 5314.

It is an arithmetic number, because the mean of its divisors is an integer number (899514).

Almost surely, 2^6658639 is an apocalyptic number.

6658639 is a deficient number, since it is larger than the sum of its proper divisors (537473).

6658639 is a wasteful number, since it uses less digits than its factorization.

6658639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1817.

The product of its digits is 233280, while the sum is 43.

The square root of 6658639 is about 2580.4338782461. The cubic root of 6658639 is about 188.1316321985.

The spelling of 6658639 in words is "six million, six hundred fifty-eight thousand, six hundred thirty-nine".