221236115 has 4 divisors (see below), whose sum is σ = 265483344. Its totient is φ = 176988888.

The previous prime is 221236027. The next prime is 221236117. The reversal of 221236115 is 511632122.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 221236115 - 2¹⁴ = 221219731 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221236117) 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, 22123607 + ... + 22123616.

It is an arithmetic number, because the mean of its divisors is an integer number (66370836).

Almost surely, 2^221236115 is an apocalyptic number.

221236115 is a deficient number, since it is larger than the sum of its proper divisors (44247229).

221236115 is an equidigital number, since it uses as much as digits as its factorization.

221236115 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44247228.

The product of its digits is 720, while the sum is 23.

The square root of 221236115 is about 14874.0080341514. The cubic root of 221236115 is about 604.8095978943.

Adding to 221236115 its reverse (511632122), we get a palindrome (732868237).

The spelling of 221236115 in words is "two hundred twenty-one million, two hundred thirty-six thousand, one hundred fifteen".