77478887477 has 12 divisors (see below), whose sum is σ = 81782532396. Its totient is φ = 73391011200.

The previous prime is 77478887471. The next prime is 77478887537.

77478887477 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 2 ways, for example, as 37367209636 + 40111677841 = 193306^2 + 200279^2 .

It is not a de Polignac number, because 77478887477 - 2⁸ = 77478887221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77478887471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4958477 + ... + 4974077.

It is an arithmetic number, because the mean of its divisors is an integer number (6815211033).

Almost surely, 2^77478887477 is an apocalyptic number.

It is an amenable number.

77478887477 is a deficient number, since it is larger than the sum of its proper divisors (4303644919).

77478887477 is a wasteful number, since it uses less digits than its factorization.

77478887477 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29396 (or 29377 counting only the distinct ones).

The product of its digits is 963780608, while the sum is 74.

The spelling of 77478887477 in words is "seventy-seven billion, four hundred seventy-eight million, eight hundred eighty-seven thousand, four hundred seventy-seven".