221206168 has 8 divisors (see below), whose sum is σ = 414761580. Its totient is φ = 110603080.

The previous prime is 221206127. The next prime is 221206169. The reversal of 221206168 is 861602122.

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×221206168² = 97864337522488448, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221206169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13825378 + ... + 13825393.

Almost surely, 2^221206168 is an apocalyptic number.

It is an amenable number.

221206168 is a deficient number, since it is larger than the sum of its proper divisors (193555412).

221206168 is a wasteful number, since it uses less digits than its factorization.

221206168 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27650777 (or 27650773 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 221206168 is about 14873.0013111006. The cubic root of 221206168 is about 604.7823072169.

The spelling of 221206168 in words is "two hundred twenty-one million, two hundred six thousand, one hundred sixty-eight".