77131312436728 has 32 divisors (see below), whose sum is σ = 164628097695360. Its totient is φ = 33535353232480.

The previous prime is 77131312436693. The next prime is 77131312436741. The reversal of 77131312436728 is 82763421313177.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19054175950 + ... + 19054179997.

It is an arithmetic number, because the mean of its divisors is an integer number (5144628052980).

Almost surely, 2^{77131312436728} is an apocalyptic number.

It is an amenable number.

77131312436728 is an abundant number, since it is smaller than the sum of its proper divisors (87496785258632).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

77131312436728 is a wasteful number, since it uses less digits than its factorization.

77131312436728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38108355987 (or 38108355983 counting only the distinct ones).

The product of its digits is 7112448, while the sum is 55.

The spelling of 77131312436728 in words is "seventy-seven trillion, one hundred thirty-one billion, three hundred twelve million, four hundred thirty-six thousand, seven hundred twenty-eight".