78287955777 has 6 divisors (see below), whose sum is σ = 113082602802. Its totient is φ = 52191970512.

The previous prime is 78287955761. The next prime is 78287955793. The reversal of 78287955777 is 77755978287.

It is an interprime number because it is at equal distance from previous prime (78287955761) and next prime (78287955793).

It can be written as a sum of positive squares in only one way, i.e., 68447117376 + 9840838401 = 261624^2 + 99201^2 .

It is not a de Polignac number, because 78287955777 - 2⁴ = 78287955761 is a prime.

It is a super-2 number, since 2×78287955777² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78287955727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4349330868 + ... + 4349330885.

It is an arithmetic number, because the mean of its divisors is an integer number (18847100467).

Almost surely, 2^78287955777 is an apocalyptic number.

It is an amenable number.

78287955777 is a deficient number, since it is larger than the sum of its proper divisors (34794647025).

78287955777 is a wasteful number, since it uses less digits than its factorization.

78287955777 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8698661759 (or 8698661756 counting only the distinct ones).

The product of its digits is 484041600, while the sum is 72.

The spelling of 78287955777 in words is "seventy-eight billion, two hundred eighty-seven million, nine hundred fifty-five thousand, seven hundred seventy-seven".