12543549779 has 2 divisors, whose sum is σ = 12543549780. Its totient is φ = 12543549778.

The previous prime is 12543549649. The next prime is 12543549793. The reversal of 12543549779 is 97794534521.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (97794534521) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12543549779 - 2¹⁶ = 12543484243 is a prime.

It is not a weakly prime, because it can be changed into another prime (12543548779) 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, 6271774889 + 6271774890.

It is an arithmetic number, because the mean of its divisors is an integer number (6271774890).

Almost surely, 2^12543549779 is an apocalyptic number.

12543549779 is a deficient number, since it is larger than the sum of its proper divisors (1).

12543549779 is an equidigital number, since it uses as much as digits as its factorization.

12543549779 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9525600, while the sum is 56.

The spelling of 12543549779 in words is "twelve billion, five hundred forty-three million, five hundred forty-nine thousand, seven hundred seventy-nine".