168187221 has 24 divisors (see below), whose sum is σ = 256256000. Its totient is φ = 106002432.

The previous prime is 168187189. The next prime is 168187223. The reversal of 168187221 is 122781861.

It is not a de Polignac number, because 168187221 - 2⁵ = 168187189 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (168187223) 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, 130860 + ... + 132138.

Almost surely, 2^168187221 is an apocalyptic number.

It is an amenable number.

168187221 is a deficient number, since it is larger than the sum of its proper divisors (88068779).

168187221 is a wasteful number, since it uses less digits than its factorization.

168187221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2073 (or 2070 counting only the distinct ones).

The product of its digits is 10752, while the sum is 36.

The square root of 168187221 is about 12968.7015926807. The cubic root of 168187221 is about 551.9897308266.

The spelling of 168187221 in words is "one hundred sixty-eight million, one hundred eighty-seven thousand, two hundred twenty-one".