665438806 has 8 divisors (see below), whose sum is σ = 1041556464. Its totient is φ = 318253320.

The previous prime is 665438801. The next prime is 665438833. The reversal of 665438806 is 608834566.

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 (46), and also a Moran number because the ratio is a prime number: 14466061 = 665438806 / (6 + 6 + 5 + 4 + 3 + 8 + 8 + 0 + 6).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665438801) 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, 7232985 + ... + 7233076.

It is an arithmetic number, because the mean of its divisors is an integer number (130194558).

Almost surely, 2^665438806 is an apocalyptic number.

665438806 is a deficient number, since it is larger than the sum of its proper divisors (376117658).

665438806 is a wasteful number, since it uses less digits than its factorization.

665438806 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14466086.

The product of its (nonzero) digits is 829440, while the sum is 46.

The square root of 665438806 is about 25796.1005967956. The cubic root of 665438806 is about 873.0438175915.

The spelling of 665438806 in words is "six hundred sixty-five million, four hundred thirty-eight thousand, eight hundred six".