31143613 has 2 divisors, whose sum is σ = 31143614. Its totient is φ = 31143612.

The previous prime is 31143601. The next prime is 31143667. The reversal of 31143613 is 31634113.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24078649 + 7064964 = 4907^2 + 2658^2 .

It is a cyclic number.

It is not a de Polignac number, because 31143613 - 2²¹ = 29046461 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31143113) 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 as a sum of consecutive naturals, namely, 15571806 + 15571807.

It is an arithmetic number, because the mean of its divisors is an integer number (15571807).

Almost surely, 2^31143613 is an apocalyptic number.

It is an amenable number.

31143613 is a deficient number, since it is larger than the sum of its proper divisors (1).

31143613 is an equidigital number, since it uses as much as digits as its factorization.

31143613 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 648, while the sum is 22.

The square root of 31143613 is about 5580.6462887375. The cubic root of 31143613 is about 314.6224181642.

Adding to 31143613 its reverse (31634113), we get a palindrome (62777726).

The spelling of 31143613 in words is "thirty-one million, one hundred forty-three thousand, six hundred thirteen".