65165440 has 128 divisors (see below), whose sum is σ = 171849600. Its totient is φ = 23519232.

The previous prime is 65165413. The next prime is 65165449. The reversal of 65165440 is 4456156.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65165449) 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, 279564 + ... + 279796.

It is an arithmetic number, because the mean of its divisors is an integer number (1342575).

Almost surely, 2^65165440 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 65165440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (85924800).

65165440 is an abundant number, since it is smaller than the sum of its proper divisors (106684160).

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

65165440 is a wasteful number, since it uses less digits than its factorization.

65165440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 294 (or 282 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 31.

The square root of 65165440 is about 8072.5113812246. The cubic root of 65165440 is about 402.4134093528.

The spelling of 65165440 in words is "sixty-five million, one hundred sixty-five thousand, four hundred forty".