165807840 has 192 divisors, whose sum is σ = 588736512. Its totient is φ = 38860800.

The previous prime is 165807833. The next prime is 165807853. The reversal of 165807840 is 48708561.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 163174 + ... + 164186.

It is an arithmetic number, because the mean of its divisors is an integer number (3066336).

Almost surely, 2^165807840 is an apocalyptic number.

165807840 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 165807840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (294368256).

165807840 is an abundant number, since it is smaller than the sum of its proper divisors (422928672).

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

165807840 is a wasteful number, since it uses less digits than its factorization.

165807840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1073 (or 1065 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 39.

The square root of 165807840 is about 12876.6393131127. The cubic root of 165807840 is about 549.3743187966.

The spelling of 165807840 in words is "one hundred sixty-five million, eight hundred seven thousand, eight hundred forty".