665723667 has 32 divisors (see below), whose sum is σ = 1050886144. Its totient is φ = 366832800.

The previous prime is 665723659. The next prime is 665723671. The reversal of 665723667 is 766327566.

It is a happy number.

665723667 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 665723667 - 2³ = 665723659 is a prime.

It is not an unprimeable number, because it can be changed into a prime (665723677) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 198192 + ... + 201522.

It is an arithmetic number, because the mean of its divisors is an integer number (32840192).

Almost surely, 2^665723667 is an apocalyptic number.

665723667 is a deficient number, since it is larger than the sum of its proper divisors (385162477).

665723667 is a wasteful number, since it uses less digits than its factorization.

665723667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3679.

The product of its digits is 1905120, while the sum is 48.

The square root of 665723667 is about 25801.6214025398. The cubic root of 665723667 is about 873.1683773325.

The spelling of 665723667 in words is "six hundred sixty-five million, seven hundred twenty-three thousand, six hundred sixty-seven".