31440143473 has 2 divisors, whose sum is σ = 31440143474. Its totient is φ = 31440143472.

The previous prime is 31440143419. The next prime is 31440143477. The reversal of 31440143473 is 37434104413.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 31139190369 + 300953104 = 176463^2 + 17348^2 .

It is an emirp because it is prime and its reverse (37434104413) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31440143473 - 2¹³ = 31440135281 is a prime.

It is not a weakly prime, because it can be changed into another prime (31440143477) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15720071736 + 15720071737.

It is an arithmetic number, because the mean of its divisors is an integer number (15720071737).

Almost surely, 2^31440143473 is an apocalyptic number.

It is an amenable number.

31440143473 is a deficient number, since it is larger than the sum of its proper divisors (1).

31440143473 is an equidigital number, since it uses as much as digits as its factorization.

31440143473 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48384, while the sum is 34.

Adding to 31440143473 its reverse (37434104413), we get a palindrome (68874247886).

The spelling of 31440143473 in words is "thirty-one billion, four hundred forty million, one hundred forty-three thousand, four hundred seventy-three".