39102705781 has 2 divisors, whose sum is σ = 39102705782. Its totient is φ = 39102705780.

The previous prime is 39102705769. The next prime is 39102705799. The reversal of 39102705781 is 18750720193.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35281611556 + 3821094225 = 187834^2 + 61815^2 .

It is an emirp because it is prime and its reverse (18750720193) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 39102705781 - 2¹¹ = 39102703733 is a prime.

It is a super-2 number, since 2×39102705781² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (39102705721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19551352890 + 19551352891.

It is an arithmetic number, because the mean of its divisors is an integer number (19551352891).

Almost surely, 2^39102705781 is an apocalyptic number.

It is an amenable number.

39102705781 is a deficient number, since it is larger than the sum of its proper divisors (1).

39102705781 is an equidigital number, since it uses as much as digits as its factorization.

39102705781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 105840, while the sum is 43.

The spelling of 39102705781 in words is "thirty-nine billion, one hundred two million, seven hundred five thousand, seven hundred eighty-one".