1115220221 has 4 divisors (see below), whose sum is σ = 1115443200. Its totient is φ = 1114997244.

The previous prime is 1115220209. The next prime is 1115220263. The reversal of 1115220221 is 1220225111.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1115220221 - 2⁶ = 1115220157 is a prime.

It is a super-2 number, since 2×1115220221² = 2487432282654577682, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1115220221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1115220521) 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, 103811 + ... + 114048.

It is an arithmetic number, because the mean of its divisors is an integer number (278860800).

Almost surely, 2^1115220221 is an apocalyptic number.

It is an amenable number.

1115220221 is a deficient number, since it is larger than the sum of its proper divisors (222979).

1115220221 is an equidigital number, since it uses as much as digits as its factorization.

1115220221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222978.

The product of its (nonzero) digits is 80, while the sum is 17.

The square root of 1115220221 is about 33394.9131006505. The cubic root of 1115220221 is about 1037.0193939103.

Adding to 1115220221 its reverse (1220225111), we get a palindrome (2335445332).

The spelling of 1115220221 in words is "one billion, one hundred fifteen million, two hundred twenty thousand, two hundred twenty-one".