11543185921 has 4 divisors (see below), whose sum is σ = 11738833200. Its totient is φ = 11347538644.

The previous prime is 11543185873. The next prime is 11543185987. The reversal of 11543185921 is 12958134511.

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.

It is a cyclic number.

It is not a de Polignac number, because 11543185921 - 2¹³ = 11543177729 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11543185021) 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, 97823551 + ... + 97823668.

It is an arithmetic number, because the mean of its divisors is an integer number (2934708300).

Almost surely, 2^11543185921 is an apocalyptic number.

It is an amenable number.

11543185921 is a deficient number, since it is larger than the sum of its proper divisors (195647279).

11543185921 is an equidigital number, since it uses as much as digits as its factorization.

11543185921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195647278.

The product of its digits is 43200, while the sum is 40.

The spelling of 11543185921 in words is "eleven billion, five hundred forty-three million, one hundred eighty-five thousand, nine hundred twenty-one".