665243807 has 8 divisors (see below), whose sum is σ = 672122880. Its totient is φ = 658392280.

The previous prime is 665243783. The next prime is 665243809. The reversal of 665243807 is 708342566.

It is a happy number.

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 665243807 - 2¹⁰ = 665242783 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665243809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 43544 + ... + 56802.

It is an arithmetic number, because the mean of its divisors is an integer number (84015360).

Almost surely, 2^665243807 is an apocalyptic number.

665243807 is a deficient number, since it is larger than the sum of its proper divisors (6879073).

665243807 is a wasteful number, since it uses less digits than its factorization.

665243807 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13773.

The product of its (nonzero) digits is 241920, while the sum is 41.

The square root of 665243807 is about 25792.3206982233. The cubic root of 665243807 is about 872.9585308595.

The spelling of 665243807 in words is "six hundred sixty-five million, two hundred forty-three thousand, eight hundred seven".