669617928 has 120 divisors (see below), whose sum is σ = 2181865950. Its totient is φ = 191310336.

The previous prime is 669617909. The next prime is 669617941. The reversal of 669617928 is 829716966.

669617928 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 371641284 + 297976644 = 19278^2 + 17262^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 21208 + ... + 42296.

Almost surely, 2^669617928 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 669617928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1090932975).

669617928 is an abundant number, since it is smaller than the sum of its proper divisors (1512248022).

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

669617928 is a wasteful number, since it uses less digits than its factorization.

669617928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21121 (or 21101 counting only the distinct ones).

The product of its digits is 1959552, while the sum is 54.

The square root of 669617928 is about 25876.9767940538. The cubic root of 669617928 is about 874.8676493153.

The spelling of 669617928 in words is "six hundred sixty-nine million, six hundred seventeen thousand, nine hundred twenty-eight".