163781920 has 48 divisors (see below), whose sum is σ = 388644480. Its totient is φ = 65223424.

The previous prime is 163781899. The next prime is 163781941. The reversal of 163781920 is 29187361.

163781920 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (163781899) and next prime (163781941).

It is a self number, because there is not a number n which added to its sum of digits gives 163781920.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36099 + ... + 40381.

It is an arithmetic number, because the mean of its divisors is an integer number (8096760).

Almost surely, 2^163781920 is an apocalyptic number.

163781920 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 163781920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (194322240).

163781920 is an abundant number, since it is smaller than the sum of its proper divisors (224862560).

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

163781920 is a wasteful number, since it uses less digits than its factorization.

163781920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4537 (or 4529 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 37.

The square root of 163781920 is about 12797.7310489008. The cubic root of 163781920 is about 547.1276368292.

The spelling of 163781920 in words is "one hundred sixty-three million, seven hundred eighty-one thousand, nine hundred twenty".