669412128 has 288 divisors, whose sum is σ = 2364199488. Its totient is φ = 163430400.

The previous prime is 669412097. The next prime is 669412147. The reversal of 669412128 is 821214966.

669412128 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Cunningham number, because it is equal to 25873²-1.

It is a super-2 number, since 2×669412128² = 896225194226976768, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 879268 + ... + 880028.

It is an arithmetic number, because the mean of its divisors is an integer number (8209026).

Almost surely, 2^669412128 is an apocalyptic number.

669412128 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 669412128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1182099744).

669412128 is an abundant number, since it is smaller than the sum of its proper divisors (1694787360).

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

669412128 is a wasteful number, since it uses less digits than its factorization.

669412128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 816 (or 801 counting only the distinct ones).

The product of its digits is 41472, while the sum is 39.

The square root of 669412128 is about 25872.9999806748. Note that the first 4 decimals coincide. The cubic root of 669412128 is about 874.7780130201.

The spelling of 669412128 in words is "six hundred sixty-nine million, four hundred twelve thousand, one hundred twenty-eight".