31131205425440 has 24 divisors (see below), whose sum is σ = 73547472817980. Its totient is φ = 12452482170112.

The previous prime is 31131205425367. The next prime is 31131205425443. The reversal of 31131205425440 is 4452450213113.

It can be written as a sum of positive squares in 2 ways, for example, as 27654009829264 + 3477195596176 = 5258708^2 + 1864724^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 31131205425440.

It is not an unprimeable number, because it can be changed into a prime (31131205425443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 97285016795 + ... + 97285017114.

Almost surely, 2^{31131205425440} is an apocalyptic number.

It is an amenable number.

31131205425440 is an abundant number, since it is smaller than the sum of its proper divisors (42416267392540).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31131205425440 is a wasteful number, since it uses less digits than its factorization.

31131205425440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194570033924 (or 194570033916 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 35.

Adding to 31131205425440 its reverse (4452450213113), we get a palindrome (35583655638553).

The spelling of 31131205425440 in words is "thirty-one trillion, one hundred thirty-one billion, two hundred five million, four hundred twenty-five thousand, four hundred forty".