165940720 has 80 divisors (see below), whose sum is σ = 423053280. Its totient is φ = 60032000.

The previous prime is 165940717. The next prime is 165940751. The reversal of 165940720 is 27049561.

It is a tau number, because it is divible by the number of its divisors (80).

It is a hoax number, since the sum of its digits (34) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 236370 + ... + 237070.

It is an arithmetic number, because the mean of its divisors is an integer number (5288166).

Almost surely, 2^165940720 is an apocalyptic number.

165940720 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 165940720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (211526640).

165940720 is an abundant number, since it is smaller than the sum of its proper divisors (257112560).

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

165940720 is a wasteful number, since it uses less digits than its factorization.

165940720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 994 (or 988 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 165940720 is about 12881.7980111474. The cubic root of 165940720 is about 549.5210375665.

The spelling of 165940720 in words is "one hundred sixty-five million, nine hundred forty thousand, seven hundred twenty".