77685863105 has 4 divisors (see below), whose sum is σ = 93223035732. Its totient is φ = 62148690480.

The previous prime is 77685863093. The next prime is 77685863107. The reversal of 77685863105 is 50136858677.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 52228703296 + 25457159809 = 228536^2 + 159553^2 .

It is not a de Polignac number, because 77685863105 - 2⁴ = 77685863089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77685863107) 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, 7768586306 + ... + 7768586315.

It is an arithmetic number, because the mean of its divisors is an integer number (23305758933).

Almost surely, 2^77685863105 is an apocalyptic number.

It is an amenable number.

77685863105 is a deficient number, since it is larger than the sum of its proper divisors (15537172627).

77685863105 is a wasteful number, since it uses less digits than its factorization.

77685863105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15537172626.

The product of its (nonzero) digits is 8467200, while the sum is 56.

The spelling of 77685863105 in words is "seventy-seven billion, six hundred eighty-five million, eight hundred sixty-three thousand, one hundred five".