168821856 has 144 divisors (see below), whose sum is σ = 560196000. Its totient is φ = 48206592.

The previous prime is 168821797. The next prime is 168821857. The reversal of 168821856 is 658128861.

It is a tau number, because it is divible by the number of its divisors (144).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (168821857) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 97930 + ... + 99638.

It is an arithmetic number, because the mean of its divisors is an integer number (3890250).

Almost surely, 2^168821856 is an apocalyptic number.

168821856 is a gapful number since it is divisible by the number (16) 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 168821856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (280098000).

168821856 is an abundant number, since it is smaller than the sum of its proper divisors (391374144).

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

168821856 is a wasteful number, since it uses less digits than its factorization.

168821856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1746 (or 1721 counting only the distinct ones).

The product of its digits is 184320, while the sum is 45.

The square root of 168821856 is about 12993.1465011367. The cubic root of 168821856 is about 552.6831491524.

The spelling of 168821856 in words is "one hundred sixty-eight million, eight hundred twenty-one thousand, eight hundred fifty-six".