72781636385839 has 2 divisors, whose sum is σ = 72781636385840. Its totient is φ = 72781636385838.

The previous prime is 72781636385797. The next prime is 72781636385851. The reversal of 72781636385839 is 93858363618727.

It is a strong prime.

It is an emirp because it is prime and its reverse (93858363618727) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72781636385839 - 2³⁵ = 72747276647471 is a prime.

It is a super-3 number, since 3×72781636385839³ (a number of 43 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72781636385879) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36390818192919 + 36390818192920.

It is an arithmetic number, because the mean of its divisors is an integer number (36390818192920).

Almost surely, 2^{72781636385839} is an apocalyptic number.

72781636385839 is a deficient number, since it is larger than the sum of its proper divisors (1).

72781636385839 is an equidigital number, since it uses as much as digits as its factorization.

72781636385839 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2194698240, while the sum is 76.

The spelling of 72781636385839 in words is "seventy-two trillion, seven hundred eighty-one billion, six hundred thirty-six million, three hundred eighty-five thousand, eight hundred thirty-nine".