1113131221 has 4 divisors (see below), whose sum is σ = 1136814912. Its totient is φ = 1089447532.

The previous prime is 1113131213. The next prime is 1113131231. The reversal of 1113131221 is 1221313111.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1221313111 = 1291 ⋅946021.

It is a cyclic number.

It is not a de Polignac number, because 1113131221 - 2³ = 1113131213 is a prime.

It is a super-2 number, since 2×1113131221² = 2478122230329901682, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1113131195 and 1113131204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1113131231) 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, 11841775 + ... + 11841868.

It is an arithmetic number, because the mean of its divisors is an integer number (284203728).

Almost surely, 2^1113131221 is an apocalyptic number.

It is an amenable number.

1113131221 is a deficient number, since it is larger than the sum of its proper divisors (23683691).

1113131221 is an equidigital number, since it uses as much as digits as its factorization.

1113131221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23683690.

The product of its digits is 36, while the sum is 16.

The square root of 1113131221 is about 33363.6212213243. The cubic root of 1113131221 is about 1036.3714837424.

Adding to 1113131221 its reverse (1221313111), we get a palindrome (2334444332).

The spelling of 1113131221 in words is "one billion, one hundred thirteen million, one hundred thirty-one thousand, two hundred twenty-one".