1121261521 has 4 divisors (see below), whose sum is σ = 1122843700. Its totient is φ = 1119679344.

The previous prime is 1121261443. The next prime is 1121261543. The reversal of 1121261521 is 1251621211.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1251621211 = 2357 ⋅531023.

It can be written as a sum of positive squares in 2 ways, for example, as 266342400 + 854919121 = 16320^2 + 29239^2 .

It is a cyclic number.

It is not a de Polignac number, because 1121261521 - 2¹¹ = 1121259473 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1121261492 and 1121261501.

It is not an unprimeable number, because it can be changed into a prime (1121261621) 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, 790026 + ... + 791443.

It is an arithmetic number, because the mean of its divisors is an integer number (280710925).

Almost surely, 2^1121261521 is an apocalyptic number.

It is an amenable number.

1121261521 is a deficient number, since it is larger than the sum of its proper divisors (1582179).

1121261521 is an equidigital number, since it uses as much as digits as its factorization.

1121261521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1582178.

The product of its digits is 240, while the sum is 22.

The square root of 1121261521 is about 33485.2433319515. The cubic root of 1121261521 is about 1038.8885812339. Note that the first 3 decimals are identical.

Adding to 1121261521 its reverse (1251621211), we get a palindrome (2372882732).

The spelling of 1121261521 in words is "one billion, one hundred twenty-one million, two hundred sixty-one thousand, five hundred twenty-one".