165723880 has 128 divisors (see below), whose sum is σ = 445824000. Its totient is φ = 55394304.

The previous prime is 165723829. The next prime is 165723881. The reversal of 165723880 is 88327561.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165723881) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 644712 + ... + 644968.

It is an arithmetic number, because the mean of its divisors is an integer number (3483000).

Almost surely, 2^165723880 is an apocalyptic number.

165723880 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 165723880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (222912000).

165723880 is an abundant number, since it is smaller than the sum of its proper divisors (280100120).

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

165723880 is a wasteful number, since it uses less digits than its factorization.

165723880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 336 (or 318 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 40.

The square root of 165723880 is about 12873.3787328735. The cubic root of 165723880 is about 549.2815743773.

The spelling of 165723880 in words is "one hundred sixty-five million, seven hundred twenty-three thousand, eight hundred eighty".