39851481613 has 2 divisors, whose sum is σ = 39851481614. Its totient is φ = 39851481612.

The previous prime is 39851481587. The next prime is 39851481643. The reversal of 39851481613 is 31618415893.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35193009604 + 4658472009 = 187598^2 + 68253^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-39851481613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (39851481643) 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, 19925740806 + 19925740807.

It is an arithmetic number, because the mean of its divisors is an integer number (19925740807).

Almost surely, 2^39851481613 is an apocalyptic number.

It is an amenable number.

39851481613 is a deficient number, since it is larger than the sum of its proper divisors (1).

39851481613 is an equidigital number, since it uses as much as digits as its factorization.

39851481613 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 622080, while the sum is 49.

The spelling of 39851481613 in words is "thirty-nine billion, eight hundred fifty-one million, four hundred eighty-one thousand, six hundred thirteen".