131163435561 has 4 divisors (see below), whose sum is σ = 174884580752. Its totient is φ = 87442290372.

The previous prime is 131163435551. The next prime is 131163435569. The reversal of 131163435561 is 165534361131.

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 not a de Polignac number, because 131163435561 - 2¹⁸ = 131163173417 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (131163435569) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21860572591 + ... + 21860572596.

It is an arithmetic number, because the mean of its divisors is an integer number (43721145188).

Almost surely, 2^131163435561 is an apocalyptic number.

It is an amenable number.

131163435561 is a deficient number, since it is larger than the sum of its proper divisors (43721145191).

131163435561 is an equidigital number, since it uses as much as digits as its factorization.

131163435561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43721145190.

The product of its digits is 97200, while the sum is 39.

Adding to 131163435561 its reverse (165534361131), we get a palindrome (296697796692).

The spelling of 131163435561 in words is "one hundred thirty-one billion, one hundred sixty-three million, four hundred thirty-five thousand, five hundred sixty-one".