77644486812 has 12 divisors (see below), whose sum is σ = 181170469256. Its totient is φ = 25881495600.

The previous prime is 77644486781. The next prime is 77644486817. The reversal of 77644486812 is 21868444677.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77644486817) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3235186939 + ... + 3235186962.

Almost surely, 2^77644486812 is an apocalyptic number.

It is an amenable number.

77644486812 is an abundant number, since it is smaller than the sum of its proper divisors (103525982444).

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

77644486812 is a wasteful number, since it uses less digits than its factorization.

77644486812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6470373908 (or 6470373906 counting only the distinct ones).

The product of its digits is 14450688, while the sum is 57.

The spelling of 77644486812 in words is "seventy-seven billion, six hundred forty-four million, four hundred eighty-six thousand, eight hundred twelve".