1665964218 has 32 divisors (see below), whose sum is σ = 3457172160. Its totient is φ = 534562560.

The previous prime is 1665964217. The next prime is 1665964231. The reversal of 1665964218 is 8124695661.

It is not an unprimeable number, because it can be changed into a prime (1665964217) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 44433 + ... + 72843.

It is an arithmetic number, because the mean of its divisors is an integer number (108036630).

Almost surely, 2^1665964218 is an apocalyptic number.

1665964218 is an abundant number, since it is smaller than the sum of its proper divisors (1791207942).

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

1665964218 is a wasteful number, since it uses less digits than its factorization.

1665964218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28782.

The product of its digits is 622080, while the sum is 48.

The square root of 1665964218 is about 40816.2249356797. The cubic root of 1665964218 is about 1185.4645090927.

The spelling of 1665964218 in words is "one billion, six hundred sixty-five million, nine hundred sixty-four thousand, two hundred eighteen".