77785557012 has 48 divisors (see below), whose sum is σ = 201706518720. Its totient is φ = 25923342816.

The previous prime is 77785556969. The next prime is 77785557013. The reversal of 77785557012 is 21075558777.

77785557012 is a `hidden beast` number, since 7 + 7 + 7 + 8 + 55 + 570 + 12 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 77785557012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77785557013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 491983 + ... + 630569.

It is an arithmetic number, because the mean of its divisors is an integer number (4202219140).

Almost surely, 2^77785557012 is an apocalyptic number.

It is an amenable number.

77785557012 is an abundant number, since it is smaller than the sum of its proper divisors (123920961708).

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

77785557012 is a wasteful number, since it uses less digits than its factorization.

77785557012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143797 (or 143789 counting only the distinct ones).

The product of its (nonzero) digits is 4802000, while the sum is 54.

The spelling of 77785557012 in words is "seventy-seven billion, seven hundred eighty-five million, five hundred fifty-seven thousand, twelve".