1105520021 has 4 divisors (see below), whose sum is σ = 1105589100. Its totient is φ = 1105450944.

The previous prime is 1105520011. The next prime is 1105520051. The reversal of 1105520021 is 1200255011.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1200255011 = 97 ⋅12373763.

It can be written as a sum of positive squares in 2 ways, for example, as 1055535121 + 49984900 = 32489^2 + 7070^2 .

It is a cyclic number.

It is not a de Polignac number, because 1105520021 - 2²² = 1101325717 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 (1105520011) 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, 3245 + ... + 47133.

It is an arithmetic number, because the mean of its divisors is an integer number (276397275).

Almost surely, 2^1105520021 is an apocalyptic number.

It is an amenable number.

1105520021 is a deficient number, since it is larger than the sum of its proper divisors (69079).

1105520021 is an equidigital number, since it uses as much as digits as its factorization.

1105520021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69078.

The product of its (nonzero) digits is 100, while the sum is 17.

The square root of 1105520021 is about 33249.3612119090. The cubic root of 1105520021 is about 1034.0039647944.

Adding to 1105520021 its reverse (1200255011), we get a palindrome (2305775032).

The spelling of 1105520021 in words is "one billion, one hundred five million, five hundred twenty thousand, twenty-one".