1665144120 has 64 divisors (see below), whose sum is σ = 5014962720. Its totient is φ = 442302464.

The previous prime is 1665144077. The next prime is 1665144139. The reversal of 1665144120 is 214415661.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 3844 + ... + 57836.

Almost surely, 2^1665144120 is an apocalyptic number.

1665144120 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 1665144120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2507481360).

1665144120 is an abundant number, since it is smaller than the sum of its proper divisors (3349818600).

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

1665144120 is a wasteful number, since it uses less digits than its factorization.

1665144120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54264 (or 54260 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 1665144120 is about 40806.1774735150. The cubic root of 1665144120 is about 1185.2699557658.

Adding to 1665144120 its reverse (214415661), we get a palindrome (1879559781).

The spelling of 1665144120 in words is "one billion, six hundred sixty-five million, one hundred forty-four thousand, one hundred twenty".