1660673664 has 336 divisors, whose sum is σ = 5490128070. Its totient is φ = 497166336.

The previous prime is 1660673647. The next prime is 1660673683. The reversal of 1660673664 is 4663760661.

1660673664 is a `hidden beast` number, since 1 + 6 + 606 + 7 + 36 + 6 + 4 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 1631513664 + 29160000 = 40392^2 + 5400^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 41 ways as a sum of consecutive naturals, for example, 44883054 + ... + 44883090.

Almost surely, 2^1660673664 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 1660673664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2745064035).

1660673664 is an abundant number, since it is smaller than the sum of its proper divisors (3829454406).

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

1660673664 is an frugal number, since it uses more digits than its factorization.

1660673664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 119 (or 55 counting only the distinct ones).

The product of its (nonzero) digits is 653184, while the sum is 45.

The square root of 1660673664 is about 40751.3639526335. The cubic root of 1660673664 is about 1184.2082966863.

The spelling of 1660673664 in words is "one billion, six hundred sixty million, six hundred seventy-three thousand, six hundred sixty-four".