11131775531 has 4 divisors (see below), whose sum is σ = 11132060064. Its totient is φ = 11131491000.

The previous prime is 11131775527. The next prime is 11131775549. The reversal of 11131775531 is 13557713111.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13557713111 = 241 ⋅56256071.

It is a cyclic number.

It is not a de Polignac number, because 11131775531 - 2² = 11131775527 is a prime.

It is a super-2 number, since 2×11131775531² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11131775491 and 11131775500.

It is not an unprimeable number, because it can be changed into a prime (11131775521) 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, 72020 + ... + 165681.

It is an arithmetic number, because the mean of its divisors is an integer number (2783015016).

Almost surely, 2^11131775531 is an apocalyptic number.

11131775531 is a deficient number, since it is larger than the sum of its proper divisors (284533).

11131775531 is an equidigital number, since it uses as much as digits as its factorization.

11131775531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 284532.

The product of its digits is 11025, while the sum is 35.

The spelling of 11131775531 in words is "eleven billion, one hundred thirty-one million, seven hundred seventy-five thousand, five hundred thirty-one".