6659659 has 4 divisors (see below), whose sum is σ = 6666480. Its totient is φ = 6652840.

The previous prime is 6659623. The next prime is 6659663. The reversal of 6659659 is 9569566.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 6659659 - 2¹³ = 6651467 is a prime.

It is a super-3 number, since 3×6659659³ (a number of 21 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6659689) 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 3 ways as a sum of consecutive naturals, for example, 1639 + ... + 4000.

It is an arithmetic number, because the mean of its divisors is an integer number (1666620).

Almost surely, 2^6659659 is an apocalyptic number.

6659659 is a deficient number, since it is larger than the sum of its proper divisors (6821).

6659659 is a wasteful number, since it uses less digits than its factorization.

6659659 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6820.

The product of its digits is 437400, while the sum is 46.

The square root of 6659659 is about 2580.6315118591. The cubic root of 6659659 is about 188.1412379887.

The spelling of 6659659 in words is "six million, six hundred fifty-nine thousand, six hundred fifty-nine".