77779677618 has 96 divisors (see below), whose sum is σ = 182233612080. Its totient is φ = 23887564800.

The previous prime is 77779677583. The next prime is 77779677641. The reversal of 77779677618 is 81677697777.

It can be written as a sum of positive squares in 8 ways, for example, as 54881027289 + 22898650329 = 234267^2 + 151323^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2736496 + ... + 2764772.

Almost surely, 2^77779677618 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77779677618, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (91116806040).

77779677618 is an abundant number, since it is smaller than the sum of its proper divisors (104453934462).

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

77779677618 is a wasteful number, since it uses less digits than its factorization.

77779677618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28492 (or 28489 counting only the distinct ones).

The product of its digits is 304946208, while the sum is 72.

The spelling of 77779677618 in words is "seventy-seven billion, seven hundred seventy-nine million, six hundred seventy-seven thousand, six hundred eighteen".