221163912 has 64 divisors (see below), whose sum is σ = 625968000. Its totient is φ = 72326592.

The previous prime is 221163893. The next prime is 221163941. The reversal of 221163912 is 219361122.

221163912 is a `hidden beast` number, since 2 + 2 + 11 + 639 + 12 = 666.

It is a super-2 number, since 2×221163912² = 97826951942287488, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1789 + ... + 21107.

It is an arithmetic number, because the mean of its divisors is an integer number (9780750).

Almost surely, 2^221163912 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221163912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (312984000).

221163912 is an abundant number, since it is smaller than the sum of its proper divisors (404804088).

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

221163912 is a wasteful number, since it uses less digits than its factorization.

221163912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19387 (or 19377 counting only the distinct ones).

The product of its digits is 1296, while the sum is 27.

The square root of 221163912 is about 14871.5806826309. The cubic root of 221163912 is about 604.7437951675.

The spelling of 221163912 in words is "two hundred twenty-one million, one hundred sixty-three thousand, nine hundred twelve".