6665618 has 8 divisors (see below), whose sum is σ = 10524720. Its totient is φ = 3157380.

The previous prime is 6665611. The next prime is 6665623. The reversal of 6665618 is 8165666.

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

It is a Harshad number since it is a multiple of its sum of digits (38), and also a Moran number because the ratio is a prime number: 175411 = 6665618 / (6 + 6 + 6 + 5 + 6 + 1 + 8).

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (6665611) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 87668 + ... + 87743.

It is an arithmetic number, because the mean of its divisors is an integer number (1315590).

Almost surely, 2^6665618 is an apocalyptic number.

6665618 is a deficient number, since it is larger than the sum of its proper divisors (3859102).

6665618 is a wasteful number, since it uses less digits than its factorization.

6665618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175432.

The product of its digits is 51840, while the sum is 38.

The square root of 6665618 is about 2581.7858160583. The cubic root of 6665618 is about 188.1973369276.

The spelling of 6665618 in words is "six million, six hundred sixty-five thousand, six hundred eighteen".