669640608 has 480 divisors, whose sum is σ = 2581818624. Its totient is φ = 165224448.

The previous prime is 669640553. The next prime is 669640633. The reversal of 669640608 is 806046966.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 4009741 + ... + 4009907.

Almost surely, 2^669640608 is an apocalyptic number.

669640608 is a gapful number since it is divisible by the number (68) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 669640608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1290909312).

669640608 is an abundant number, since it is smaller than the sum of its proper divisors (1912178016).

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

669640608 is a wasteful number, since it uses less digits than its factorization.

669640608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 226 (or 209 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 45.

The square root of 669640608 is about 25877.4150177331. The cubic root of 669640608 is about 874.8775264773.

The spelling of 669640608 in words is "six hundred sixty-nine million, six hundred forty thousand, six hundred eight".