1665238180 has 24 divisors (see below), whose sum is σ = 3649044672. Its totient is φ = 637134432.

The previous prime is 1665238171. The next prime is 1665238181. The reversal of 1665238180 is 818325661.

It is a super-2 number, since 2×1665238180² = 5546036392259424800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1665238181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1809582 + ... + 1810501.

It is an arithmetic number, because the mean of its divisors is an integer number (152043528).

Almost surely, 2^1665238180 is an apocalyptic number.

1665238180 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1665238180 is an abundant number, since it is smaller than the sum of its proper divisors (1983806492).

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

1665238180 is a wasteful number, since it uses less digits than its factorization.

1665238180 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3620115 (or 3620113 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 40.

The square root of 1665238180 is about 40807.3299788163. The cubic root of 1665238180 is about 1185.2922730318.

The spelling of 1665238180 in words is "one billion, six hundred sixty-five million, two hundred thirty-eight thousand, one hundred eighty".