1665086580 has 72 divisors (see below), whose sum is σ = 5187290472. Its totient is φ = 432020736.

The previous prime is 1665086557. The next prime is 1665086623. The reversal of 1665086580 is 856805661.

1665086580 is a `hidden beast` number, since 1 + 6 + 6 + 508 + 65 + 80 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 646583184 + 1018503396 = 25428^2 + 31914^2 .

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

It is a congruent number.

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 23 ways as a sum of consecutive naturals, for example, 118347 + ... + 131666.

It is an arithmetic number, because the mean of its divisors is an integer number (72045701).

Almost surely, 2^1665086580 is an apocalyptic number.

1665086580 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1665086580 is an abundant number, since it is smaller than the sum of its proper divisors (3522203892).

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

1665086580 is a wasteful number, since it uses less digits than its factorization.

1665086580 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250065 (or 250060 counting only the distinct ones).

The product of its (nonzero) digits is 345600, while the sum is 45.

The square root of 1665086580 is about 40805.4724271145. The cubic root of 1665086580 is about 1185.2563030499.

The spelling of 1665086580 in words is "one billion, six hundred sixty-five million, eighty-six thousand, five hundred eighty".