2165240240 has 80 divisors (see below), whose sum is σ = 5263163136. Its totient is φ = 826848000.

The previous prime is 2165240237. The next prime is 2165240249. The reversal of 2165240240 is 420425612.

It is a tau number, because it is divible by the number of its divisors (80).

It is not an unprimeable number, because it can be changed into a prime (2165240249) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1491515 + ... + 1492965.

Almost surely, 2^2165240240 is an apocalyptic number.

2165240240 is a gapful number since it is divisible by the number (20) 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 2165240240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2631581568).

2165240240 is an abundant number, since it is smaller than the sum of its proper divisors (3097922896).

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

2165240240 is a wasteful number, since it uses less digits than its factorization.

2165240240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2298 (or 2292 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 26.

The square root of 2165240240 is about 46532.1420095830. The cubic root of 2165240240 is about 1293.7053174763.

Adding to 2165240240 its reverse (420425612), we get a palindrome (2585665852).

The spelling of 2165240240 in words is "two billion, one hundred sixty-five million, two hundred forty thousand, two hundred forty".