11581747493 has 4 divisors (see below), whose sum is σ = 11771612268. Its totient is φ = 11391882720.

The previous prime is 11581747459. The next prime is 11581747537. The reversal of 11581747493 is 39474718511.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 39474718511 = 1439 ⋅27432049.

It can be written as a sum of positive squares in 2 ways, for example, as 389588644 + 11192158849 = 19738^2 + 105793^2 .

It is a cyclic number.

It is not a de Polignac number, because 11581747493 - 2²⁸ = 11313312037 is a prime.

It is a super-2 number, since 2×11581747493² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11581747433) 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, 94932296 + ... + 94932417.

It is an arithmetic number, because the mean of its divisors is an integer number (2942903067).

Almost surely, 2^11581747493 is an apocalyptic number.

It is an amenable number.

11581747493 is a deficient number, since it is larger than the sum of its proper divisors (189864775).

11581747493 is an equidigital number, since it uses as much as digits as its factorization.

11581747493 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189864774.

The product of its digits is 846720, while the sum is 50.

The spelling of 11581747493 in words is "eleven billion, five hundred eighty-one million, seven hundred forty-seven thousand, four hundred ninety-three".