1808947339649 has 2 divisors, whose sum is σ = 1808947339650. Its totient is φ = 1808947339648.

The previous prime is 1808947339603. The next prime is 1808947339679. The reversal of 1808947339649 is 9469337498081.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1255448539024 + 553498800625 = 1120468^2 + 743975^2 .

It is a cyclic number.

It is not a de Polignac number, because 1808947339649 - 2¹² = 1808947335553 is a prime.

It is not a weakly prime, because it can be changed into another prime (1808947339679) 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, 904473669824 + 904473669825.

It is an arithmetic number, because the mean of its divisors is an integer number (904473669825).

Almost surely, 2^{1808947339649} is an apocalyptic number.

It is an amenable number.

1808947339649 is a deficient number, since it is larger than the sum of its proper divisors (1).

1808947339649 is an equidigital number, since it uses as much as digits as its factorization.

1808947339649 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 282175488, while the sum is 71.

The spelling of 1808947339649 in words is "one trillion, eight hundred eight billion, nine hundred forty-seven million, three hundred thirty-nine thousand, six hundred forty-nine".