165864560 has 40 divisors (see below), whose sum is σ = 392921280. Its totient is φ = 65092352.

The previous prime is 165864533. The next prime is 165864577. The reversal of 165864560 is 65468561.

It is a happy number.

165864560 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×165864560² = 55022104527987200, which contains 22 as substring.

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 7 ways as a sum of consecutive naturals, for example, 15320 + ... + 23799.

It is an arithmetic number, because the mean of its divisors is an integer number (9823032).

Almost surely, 2^165864560 is an apocalyptic number.

165864560 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

165864560 is an abundant number, since it is smaller than the sum of its proper divisors (227056720).

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

165864560 is a wasteful number, since it uses less digits than its factorization.

165864560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39185 (or 39179 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 41.

The square root of 165864560 is about 12878.8415628115. The cubic root of 165864560 is about 549.4369554787.

The spelling of 165864560 in words is "one hundred sixty-five million, eight hundred sixty-four thousand, five hundred sixty".