1113220021 has 4 divisors (see below), whose sum is σ = 1113287500. Its totient is φ = 1113152544.

The previous prime is 1113220001. The next prime is 1113220039. The reversal of 1113220021 is 1200223111.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 485717521 + 627502500 = 22039^2 + 25050^2 .

It is a cyclic number.

It is not a de Polignac number, because 1113220021 - 2⁷ = 1113219893 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1113219983 and 1113220010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1113220001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9355 + ... + 48103.

It is an arithmetic number, because the mean of its divisors is an integer number (278321875).

Almost surely, 2^1113220021 is an apocalyptic number.

It is an amenable number.

1113220021 is a deficient number, since it is larger than the sum of its proper divisors (67479).

1113220021 is an equidigital number, since it uses as much as digits as its factorization.

1113220021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67478.

The product of its (nonzero) digits is 24, while the sum is 13.

The square root of 1113220021 is about 33364.9519855791. The cubic root of 1113220021 is about 1036.3990418412.

Adding to 1113220021 its reverse (1200223111), we get a palindrome (2313443132).

The spelling of 1113220021 in words is "one billion, one hundred thirteen million, two hundred twenty thousand, twenty-one".