11521644523 has 4 divisors (see below), whose sum is σ = 11918942640. Its totient is φ = 11124346408.

The previous prime is 11521644521. The next prime is 11521644527. The reversal of 11521644523 is 32544612511.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32544612511 = 155219 ⋅209669.

It is not a de Polignac number, because 11521644523 - 2¹ = 11521644521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11521644521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 198649015 + ... + 198649072.

It is an arithmetic number, because the mean of its divisors is an integer number (2979735660).

Almost surely, 2^11521644523 is an apocalyptic number.

11521644523 is a deficient number, since it is larger than the sum of its proper divisors (397298117).

11521644523 is an equidigital number, since it uses as much as digits as its factorization.

11521644523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 397298116.

The product of its digits is 28800, while the sum is 34.

The spelling of 11521644523 in words is "eleven billion, five hundred twenty-one million, six hundred forty-four thousand, five hundred twenty-three".