165239440 has 20 divisors (see below), whose sum is σ = 384181884. Its totient is φ = 66095744.

The previous prime is 165239413. The next prime is 165239441. The reversal of 165239440 is 44932561.

It is a happy number.

165239440 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 62663056 + 102576384 = 7916^2 + 10128^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a junction number, because it is equal to n+sod(n) for n = 165239396 and 165239405.

It is not an unprimeable number, because it can be changed into a prime (165239441) 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 3 ways as a sum of consecutive naturals, for example, 1032667 + ... + 1032826.

Almost surely, 2^165239440 is an apocalyptic number.

165239440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

165239440 is an abundant number, since it is smaller than the sum of its proper divisors (218942444).

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

165239440 is a wasteful number, since it uses less digits than its factorization.

165239440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2065506 (or 2065500 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 34.

The square root of 165239440 is about 12854.5493892240. The cubic root of 165239440 is about 548.7458365232.

The spelling of 165239440 in words is "one hundred sixty-five million, two hundred thirty-nine thousand, four hundred forty".