669909408 has 192 divisors, whose sum is σ = 2125025280. Its totient is φ = 180652032.

The previous prime is 669909403. The next prime is 669909413. The reversal of 669909408 is 804909966.

It is an interprime number because it is at equal distance from previous prime (669909403) and next prime (669909413).

It is a super-2 number, since 2×669909408² = 897557229853820928, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (669909403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1375341 + ... + 1375827.

It is an arithmetic number, because the mean of its divisors is an integer number (11067840).

Almost surely, 2^669909408 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 669909408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1062512640).

669909408 is an abundant number, since it is smaller than the sum of its proper divisors (1455115872).

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

669909408 is a wasteful number, since it uses less digits than its factorization.

669909408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 619 (or 611 counting only the distinct ones).

The product of its (nonzero) digits is 839808, while the sum is 51.

The square root of 669909408 is about 25882.6082147839. The cubic root of 669909408 is about 874.9945721568.

The spelling of 669909408 in words is "six hundred sixty-nine million, nine hundred nine thousand, four hundred eight".