667878609 has 8 divisors (see below), whose sum is σ = 942887520. Its totient is φ = 419061056.

The previous prime is 667878581. The next prime is 667878637. The reversal of 667878609 is 906878766.

667878609 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (667878581) and next prime (667878637).

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 667878609 - 2¹⁹ = 667354321 is a prime.

It is not an unprimeable number, because it can be changed into a prime (667874609) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6547779 + ... + 6547880.

It is an arithmetic number, because the mean of its divisors is an integer number (117860940).

Almost surely, 2^667878609 is an apocalyptic number.

It is an amenable number.

667878609 is a deficient number, since it is larger than the sum of its proper divisors (275008911).

667878609 is a wasteful number, since it uses less digits than its factorization.

667878609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13095679.

The product of its (nonzero) digits is 6096384, while the sum is 57.

The square root of 667878609 is about 25843.3474805413. The cubic root of 667878609 is about 874.1095088536.

The spelling of 667878609 in words is "six hundred sixty-seven million, eight hundred seventy-eight thousand, six hundred nine".