1101131221 has 4 divisors (see below), whose sum is σ = 1103040172. Its totient is φ = 1099222272.

The previous prime is 1101131177. The next prime is 1101131237. The reversal of 1101131221 is 1221311011.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1221311011 = 1021 ⋅1196191.

It can be written as a sum of positive squares in 2 ways, for example, as 923308996 + 177822225 = 30386^2 + 13335^2 .

It is a cyclic number.

It is not a de Polignac number, because 1101131221 - 2⁷ = 1101131093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1101131281) 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, 953610 + ... + 954763.

It is an arithmetic number, because the mean of its divisors is an integer number (275760043).

Almost surely, 2^1101131221 is an apocalyptic number.

It is an amenable number.

1101131221 is a deficient number, since it is larger than the sum of its proper divisors (1908951).

1101131221 is an equidigital number, since it uses as much as digits as its factorization.

1101131221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1908950.

The product of its (nonzero) digits is 12, while the sum is 13.

The square root of 1101131221 is about 33183.2973195853. The cubic root of 1101131221 is about 1032.6338539047.

Adding to 1101131221 its reverse (1221311011), we get a palindrome (2322442232).

The spelling of 1101131221 in words is "one billion, one hundred one million, one hundred thirty-one thousand, two hundred twenty-one".