31885281361 has 4 divisors (see below), whose sum is σ = 31885762612. Its totient is φ = 31884800112.

The previous prime is 31885281347. The next prime is 31885281397. The reversal of 31885281361 is 16318258813.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5582928961 + 26302352400 = 74719^2 + 162180^2 .

It is a cyclic number.

It is not a de Polignac number, because 31885281361 - 2²⁹ = 31348410449 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31885281161) 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, 121626 + ... + 280291.

It is an arithmetic number, because the mean of its divisors is an integer number (7971440653).

Almost surely, 2^31885281361 is an apocalyptic number.

It is an amenable number.

31885281361 is a deficient number, since it is larger than the sum of its proper divisors (481251).

31885281361 is an equidigital number, since it uses as much as digits as its factorization.

31885281361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 481250.

The product of its digits is 276480, while the sum is 46.

The spelling of 31885281361 in words is "thirty-one billion, eight hundred eighty-five million, two hundred eighty-one thousand, three hundred sixty-one".