669726144 has 280 divisors, whose sum is σ = 2137611168. Its totient is φ = 206807040.

The previous prime is 669726143. The next prime is 669726181. The reversal of 669726144 is 441627966.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 669726144.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (669726143) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 4888444 + ... + 4888580.

Almost surely, 2^669726144 is an apocalyptic number.

669726144 is a gapful number since it is divisible by the number (64) 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 669726144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1068805584).

669726144 is an abundant number, since it is smaller than the sum of its proper divisors (1467885024).

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

669726144 is a wasteful number, since it uses less digits than its factorization.

669726144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 225 (or 206 counting only the distinct ones).

The product of its digits is 435456, while the sum is 45.

The square root of 669726144 is about 25879.0676802701. The cubic root of 669726144 is about 874.9147754818.

The spelling of 669726144 in words is "six hundred sixty-nine million, seven hundred twenty-six thousand, one hundred forty-four".