669278678 has 32 divisors (see below), whose sum is σ = 1092787200. Its totient is φ = 306244224.

The previous prime is 669278677. The next prime is 669278693. The reversal of 669278678 is 876872966.

It is a Smith number, since the sum of its digits (59) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (669278671) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 178103 + ... + 181821.

It is an arithmetic number, because the mean of its divisors is an integer number (34149600).

Almost surely, 2^669278678 is an apocalyptic number.

669278678 is a deficient number, since it is larger than the sum of its proper divisors (423508522).

669278678 is a wasteful number, since it uses less digits than its factorization.

669278678 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3884.

The product of its digits is 12192768, while the sum is 59.

The square root of 669278678 is about 25870.4209088295. The cubic root of 669278678 is about 874.7198789852.

The spelling of 669278678 in words is "six hundred sixty-nine million, two hundred seventy-eight thousand, six hundred seventy-eight".