165725520 has 160 divisors (see below), whose sum is σ = 549607680. Its totient is φ = 41164800.

The previous prime is 165725509. The next prime is 165725531. The reversal of 165725520 is 25527561.

165725520 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (165725509) and next prime (165725531).

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, 615946 + ... + 616214.

It is an arithmetic number, because the mean of its divisors is an integer number (3435048).

Almost surely, 2^165725520 is an apocalyptic number.

165725520 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 165725520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (274803840).

165725520 is an abundant number, since it is smaller than the sum of its proper divisors (383882160).

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

165725520 is a wasteful number, since it uses less digits than its factorization.

165725520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 453 (or 447 counting only the distinct ones).

The product of its (nonzero) digits is 21000, while the sum is 33.

The square root of 165725520 is about 12873.4424300573. The cubic root of 165725520 is about 549.2833862643.

The spelling of 165725520 in words is "one hundred sixty-five million, seven hundred twenty-five thousand, five hundred twenty".