669989670 has 128 divisors (see below), whose sum is σ = 1918328832. Its totient is φ = 146534400.

The previous prime is 669989641. The next prime is 669989681. The reversal of 669989670 is 76989966.

It is a happy number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 630940 + ... + 632000.

It is an arithmetic number, because the mean of its divisors is an integer number (14986944).

Almost surely, 2^669989670 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 669989670, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (959164416).

669989670 is an abundant number, since it is smaller than the sum of its proper divisors (1248339162).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

669989670 is a wasteful number, since it uses less digits than its factorization.

669989670 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1206.

The product of its (nonzero) digits is 8817984, while the sum is 60.

The square root of 669989670 is about 25884.1586689620. The cubic root of 669989670 is about 875.0295151949.

It can be divided in two parts, 6699896 and 70, that added together give a palindrome (6699966).

The spelling of 669989670 in words is "six hundred sixty-nine million, nine hundred eighty-nine thousand, six hundred seventy".