165559610880 has 320 divisors, whose sum is σ = 622678985280. Its totient is φ = 41551921152.

The previous prime is 165559610869. The next prime is 165559610899. The reversal of 165559610880 is 88016955561.

165559610880 is a `hidden beast` number, since 1 + 6 + 5 + 559 + 6 + 1 + 0 + 8 + 80 = 666.

It is a tau number, because it is divible by the number of its divisors (320).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1104592 + ... + 1245488.

It is an arithmetic number, because the mean of its divisors is an integer number (1945871829).

Almost surely, 2^165559610880 is an apocalyptic number.

165559610880 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 165559610880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (311339492640).

165559610880 is an abundant number, since it is smaller than the sum of its proper divisors (457119374400).

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

165559610880 is a wasteful number, since it uses less digits than its factorization.

165559610880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140946 (or 140924 counting only the distinct ones).

The product of its (nonzero) digits is 2592000, while the sum is 54.

The spelling of 165559610880 in words is "one hundred sixty-five billion, five hundred fifty-nine million, six hundred ten thousand, eight hundred eighty".