1665668160 has 336 divisors, whose sum is σ = 6535344816. Its totient is φ = 385744896.

The previous prime is 1665668159. The next prime is 1665668171. The reversal of 1665668160 is 618665661.

1665668160 is a `hidden beast` number, since 1 + 6 + 6 + 566 + 81 + 6 + 0 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 63107136 + 1602561024 = 7944^2 + 40032^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

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, 635172 + ... + 637788.

It is an arithmetic number, because the mean of its divisors is an integer number (19450431).

Almost surely, 2^1665668160 is an apocalyptic number.

1665668160 is a gapful number since it is divisible by the number (10) 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 1665668160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3267672408).

1665668160 is an abundant number, since it is smaller than the sum of its proper divisors (4869676656).

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

1665668160 is a wasteful number, since it uses less digits than its factorization.

1665668160 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2670 (or 2657 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The square root of 1665668160 is about 40812.5980550124. The cubic root of 1665668160 is about 1185.3942820854.

The spelling of 1665668160 in words is "one billion, six hundred sixty-five million, six hundred sixty-eight thousand, one hundred sixty".