221216042 has 8 divisors (see below), whose sum is σ = 331980132. Its totient is φ = 110556000.

The previous prime is 221216041. The next prime is 221216059. The reversal of 221216042 is 240612122.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 221087161 + 128881 = 14869^2 + 359^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (221216041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20459 + ... + 29342.

Almost surely, 2^221216042 is an apocalyptic number.

221216042 is a deficient number, since it is larger than the sum of its proper divisors (110764090).

221216042 is a wasteful number, since it uses less digits than its factorization.

221216042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52024.

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 221216042 is about 14873.3332511579. Note that the first 3 decimals coincide. The cubic root of 221216042 is about 604.7913056574.

Adding to 221216042 its reverse (240612122), we get a palindrome (461828164).

The spelling of 221216042 in words is "two hundred twenty-one million, two hundred sixteen thousand, forty-two".