168091920 has 240 divisors, whose sum is σ = 618388992. Its totient is φ = 40734720.

The previous prime is 168091909. The next prime is 168091921. The reversal of 168091920 is 29190861.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (168091921) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 379219 + ... + 379661.

Almost surely, 2^168091920 is an apocalyptic number.

168091920 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 168091920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (309194496).

168091920 is an abundant number, since it is smaller than the sum of its proper divisors (450297072).

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

168091920 is a wasteful number, since it uses less digits than its factorization.

168091920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 510 (or 501 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 36.

The square root of 168091920 is about 12965.0268029033. The cubic root of 168091920 is about 551.8854519717.

The spelling of 168091920 in words is "one hundred sixty-eight million, ninety-one thousand, nine hundred twenty".