165705940 has 24 divisors (see below), whose sum is σ = 349793640. Its totient is φ = 65937408.

The previous prime is 165705937. The next prime is 165705949. The reversal of 165705940 is 49507561.

It can be written as a sum of positive squares in 4 ways, for example, as 6290064 + 159415876 = 2508^2 + 12626^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 165705940.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165705949) 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 7 ways as a sum of consecutive naturals, for example, 17605 + ... + 25324.

It is an arithmetic number, because the mean of its divisors is an integer number (14574735).

Almost surely, 2^165705940 is an apocalyptic number.

165705940 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

165705940 is an abundant number, since it is smaller than the sum of its proper divisors (184087700).

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

165705940 is a wasteful number, since it uses less digits than its factorization.

165705940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43131 (or 43129 counting only the distinct ones).

The product of its (nonzero) digits is 37800, while the sum is 37.

The square root of 165705940 is about 12872.6819272442. The cubic root of 165705940 is about 549.2617533211.

The spelling of 165705940 in words is "one hundred sixty-five million, seven hundred five thousand, nine hundred forty".