78778462249 has 2 divisors, whose sum is σ = 78778462250. Its totient is φ = 78778462248.

The previous prime is 78778462211. The next prime is 78778462303. The reversal of 78778462249 is 94226487787.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 50161665024 + 28616797225 = 223968^2 + 169165^2 .

It is a cyclic number.

It is not a de Polignac number, because 78778462249 - 2³¹ = 76630978601 is a prime.

It is a super-2 number, since 2×78778462249² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (78778462649) 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, 39389231124 + 39389231125.

It is an arithmetic number, because the mean of its divisors is an integer number (39389231125).

Almost surely, 2^78778462249 is an apocalyptic number.

It is an amenable number.

78778462249 is a deficient number, since it is larger than the sum of its proper divisors (1).

78778462249 is an equidigital number, since it uses as much as digits as its factorization.

78778462249 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 75866112, while the sum is 64.

The spelling of 78778462249 in words is "seventy-eight billion, seven hundred seventy-eight million, four hundred sixty-two thousand, two hundred forty-nine".