668000665 has 8 divisors (see below), whose sum is σ = 801760968. Its totient is φ = 534293760.

The previous prime is 668000647. The next prime is 668000681. The reversal of 668000665 is 566000866.

668000665 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 45198729 + 622801936 = 6723^2 + 24956^2 .

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

It is not a de Polignac number, because 668000665 - 2⁵ = 668000633 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23355 + ... + 43375.

It is an arithmetic number, because the mean of its divisors is an integer number (100220121).

Almost surely, 2^668000665 is an apocalyptic number.

It is an amenable number.

668000665 is a deficient number, since it is larger than the sum of its proper divisors (133760303).

668000665 is a wasteful number, since it uses less digits than its factorization.

668000665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26699.

The product of its (nonzero) digits is 51840, while the sum is 37.

The square root of 668000665 is about 25845.7088314482. The cubic root of 668000665 is about 874.1627539644.

The spelling of 668000665 in words is "six hundred sixty-eight million, six hundred sixty-five", and thus it is an aban number.