165040865280 has 960 divisors, whose sum is σ = 634159411200. Its totient is φ = 40627077120.

The previous prime is 165040865221. The next prime is 165040865287. The reversal of 165040865280 is 82568040561.

165040865280 is a `hidden beast` number, since 1 + 6 + 5 + 0 + 40 + 86 + 528 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (960).

It is a super-2 number, since 2×165040865280² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165040865287) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1988444119 + ... + 1988444201.

It is an arithmetic number, because the mean of its divisors is an integer number (660582720).

Almost surely, 2^165040865280 is an apocalyptic number.

165040865280 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 165040865280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (317079705600).

165040865280 is an abundant number, since it is smaller than the sum of its proper divisors (469118545920).

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

165040865280 is an equidigital number, since it uses as much as digits as its factorization.

165040865280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185 (or 153 counting only the distinct ones).

The product of its (nonzero) digits is 460800, while the sum is 45.

The spelling of 165040865280 in words is "one hundred sixty-five billion, forty million, eight hundred sixty-five thousand, two hundred eighty".