163505555501440 has 128 divisors (see below), whose sum is σ = 394928472597120. Its totient is φ = 64724971683840.

The previous prime is 163505555501437. The next prime is 163505555501447. The reversal of 163505555501440 is 44105555505361.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (163505555501447) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1737137580 + ... + 1737231700.

It is an arithmetic number, because the mean of its divisors is an integer number (3085378692165).

Almost surely, 2^{163505555501440} is an apocalyptic number.

163505555501440 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 163505555501440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (197464236298560).

163505555501440 is an abundant number, since it is smaller than the sum of its proper divisors (231422917095680).

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

163505555501440 is an equidigital number, since it uses as much as digits as its factorization.

163505555501440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122220 (or 122208 counting only the distinct ones).

The product of its (nonzero) digits is 4500000, while the sum is 49.

The spelling of 163505555501440 in words is "one hundred sixty-three trillion, five hundred five billion, five hundred fifty-five million, five hundred one thousand, four hundred forty".