163531205920 has 96 divisors (see below), whose sum is σ = 398997446400. Its totient is φ = 63301134336.

The previous prime is 163531205899. The next prime is 163531205923. The reversal of 163531205920 is 29502135361.

It is a self number, because there is not a number n which added to its sum of digits gives 163531205920.

It is not an unprimeable number, because it can be changed into a prime (163531205923) 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, 547111 + ... + 791449.

It is an arithmetic number, because the mean of its divisors is an integer number (4156223400).

Almost surely, 2^163531205920 is an apocalyptic number.

163531205920 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 163531205920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (199498723200).

163531205920 is an abundant number, since it is smaller than the sum of its proper divisors (235466240480).

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

163531205920 is a wasteful number, since it uses less digits than its factorization.

163531205920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 244490 (or 244482 counting only the distinct ones).

The product of its (nonzero) digits is 48600, while the sum is 37.

The spelling of 163531205920 in words is "one hundred sixty-three billion, five hundred thirty-one million, two hundred five thousand, nine hundred twenty".