669770640 has 320 divisors, whose sum is σ = 2876958720. Its totient is φ = 139138560.

The previous prime is 669770639. The next prime is 669770671. The reversal of 669770640 is 46077966.

It is a Harshad number since it is a multiple of its sum of digits (45).

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 63 ways as a sum of consecutive naturals, for example, 164307 + ... + 168333.

It is an arithmetic number, because the mean of its divisors is an integer number (8990496).

Almost surely, 2^669770640 is an apocalyptic number.

669770640 is a gapful number since it is divisible by the number (60) 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 669770640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1438479360).

669770640 is an abundant number, since it is smaller than the sum of its proper divisors (2207188080).

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

669770640 is a wasteful number, since it uses less digits than its factorization.

669770640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4067 (or 4055 counting only the distinct ones).

The product of its (nonzero) digits is 381024, while the sum is 45.

The square root of 669770640 is about 25879.9273569305. The cubic root of 669770640 is about 874.9341512351.

The spelling of 669770640 in words is "six hundred sixty-nine million, seven hundred seventy thousand, six hundred forty".