165405240 has 768 divisors, whose sum is σ = 792529920. Its totient is φ = 29859840.

The previous prime is 165405217. The next prime is 165405263. The reversal of 165405240 is 42504561.

165405240 is a `hidden beast` number, since 1 + 654 + 0 + 5 + 2 + 4 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (165405217) and next prime (165405263).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 9729712 + ... + 9729728.

It is an arithmetic number, because the mean of its divisors is an integer number (1031940).

Almost surely, 2^165405240 is an apocalyptic number.

165405240 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 165405240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (396264960).

165405240 is an abundant number, since it is smaller than the sum of its proper divisors (627124680).

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

165405240 is a wasteful number, since it uses less digits than its factorization.

165405240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74 (or 58 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 27.

The square root of 165405240 is about 12860.9968509443. The cubic root of 165405240 is about 548.9293109737.

The spelling of 165405240 in words is "one hundred sixty-five million, four hundred five thousand, two hundred forty".