77969378789 has 2 divisors, whose sum is σ = 77969378790. Its totient is φ = 77969378788.

The previous prime is 77969378771. The next prime is 77969378797. The reversal of 77969378789 is 98787396977.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 77934213889 + 35164900 = 279167^2 + 5930^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77969378789 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77969378089) 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, 38984689394 + 38984689395.

It is an arithmetic number, because the mean of its divisors is an integer number (38984689395).

Almost surely, 2^77969378789 is an apocalyptic number.

It is an amenable number.

77969378789 is a deficient number, since it is larger than the sum of its proper divisors (1).

77969378789 is an equidigital number, since it uses as much as digits as its factorization.

77969378789 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2016379008, while the sum is 80.

The spelling of 77969378789 in words is "seventy-seven billion, nine hundred sixty-nine million, three hundred seventy-eight thousand, seven hundred eighty-nine".