165409440 has 192 divisors, whose sum is σ = 627056640. Its totient is φ = 35804160.

The previous prime is 165409427. The next prime is 165409501. The reversal of 165409440 is 44904561.

It is a super-2 number, since 2×165409440² = 54720565682227200, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 62545 + ... + 65135.

It is an arithmetic number, because the mean of its divisors is an integer number (3265920).

Almost surely, 2^165409440 is an apocalyptic number.

165409440 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 165409440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (313528320).

165409440 is an abundant number, since it is smaller than the sum of its proper divisors (461647200).

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

165409440 is a wasteful number, since it uses less digits than its factorization.

165409440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2635 (or 2627 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 33.

The square root of 165409440 is about 12861.1601342958. The cubic root of 165409440 is about 548.9339571055.

The spelling of 165409440 in words is "one hundred sixty-five million, four hundred nine thousand, four hundred forty".