671666688 has 320 divisors, whose sum is σ = 2482698240. Its totient is φ = 174182400.

The previous prime is 671666683. The next prime is 671666711. The reversal of 671666688 is 886666176.

It is a super-2 number, since 2×671666688² = 902272279537778688, which contains 22 as substring.

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 not an unprimeable number, because it can be changed into a prime (671666683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1064133 + ... + 1064763.

It is an arithmetic number, because the mean of its divisors is an integer number (7758432).

Almost surely, 2^671666688 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 671666688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1241349120).

671666688 is an abundant number, since it is smaller than the sum of its proper divisors (1811031552).

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

671666688 is a wasteful number, since it uses less digits than its factorization.

671666688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 676 (or 654 counting only the distinct ones).

The product of its digits is 3483648, while the sum is 54.

The square root of 671666688 is about 25916.5331014779. The cubic root of 671666688 is about 875.7589879285.

The spelling of 671666688 in words is "six hundred seventy-one million, six hundred sixty-six thousand, six hundred eighty-eight".