12781831750613 has 2 divisors, whose sum is σ = 12781831750614. Its totient is φ = 12781831750612.

The previous prime is 12781831750609. The next prime is 12781831750621. The reversal of 12781831750613 is 31605713818721.

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., 12632892101284 + 148939649329 = 3554278^2 + 385927^2 .

It is a cyclic number.

It is not a de Polignac number, because 12781831750613 - 2² = 12781831750609 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12781831450613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6390915875306 + 6390915875307.

It is an arithmetic number, because the mean of its divisors is an integer number (6390915875307).

Almost surely, 2^{12781831750613} is an apocalyptic number.

It is an amenable number.

12781831750613 is a deficient number, since it is larger than the sum of its proper divisors (1).

12781831750613 is an equidigital number, since it uses as much as digits as its factorization.

12781831750613 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1693440, while the sum is 53.

The spelling of 12781831750613 in words is "twelve trillion, seven hundred eighty-one billion, eight hundred thirty-one million, seven hundred fifty thousand, six hundred thirteen".