666683648 has 36 divisors (see below), whose sum is σ = 1340547180. Its totient is φ = 330891264.

The previous prime is 666683623. The next prime is 666683783. The reversal of 666683648 is 846386666.

It can be written as a sum of positive squares in 2 ways, for example, as 482593024 + 184090624 = 21968^2 + 13568^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 666683648.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 25568 + ... + 44576.

Almost surely, 2^666683648 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 666683648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (670273590).

666683648 is an abundant number, since it is smaller than the sum of its proper divisors (673863532).

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

666683648 is a wasteful number, since it uses less digits than its factorization.

666683648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19162 (or 19148 counting only the distinct ones).

The product of its digits is 5971968, while the sum is 53.

The square root of 666683648 is about 25820.2178147281. The cubic root of 666683648 is about 873.5878819539.

The spelling of 666683648 in words is "six hundred sixty-six million, six hundred eighty-three thousand, six hundred forty-eight".