31818044813 has 2 divisors, whose sum is σ = 31818044814. Its totient is φ = 31818044812.

The previous prime is 31818044759. The next prime is 31818044837. The reversal of 31818044813 is 31844081813.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 22320957604 + 9497087209 = 149402^2 + 97453^2 .

It is an emirp because it is prime and its reverse (31844081813) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31818044813 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31818044893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15909022406 + 15909022407.

It is an arithmetic number, because the mean of its divisors is an integer number (15909022407).

Almost surely, 2^31818044813 is an apocalyptic number.

It is an amenable number.

31818044813 is a deficient number, since it is larger than the sum of its proper divisors (1).

31818044813 is an equidigital number, since it uses as much as digits as its factorization.

31818044813 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 73728, while the sum is 41.

The spelling of 31818044813 in words is "thirty-one billion, eight hundred eighteen million, forty-four thousand, eight hundred thirteen".