77865603856555 has 4 divisors (see below), whose sum is σ = 93438724627872. Its totient is φ = 62292483085240.

The previous prime is 77865603856517. The next prime is 77865603856577. The reversal of 77865603856555 is 55565830656877.

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

It is not a de Polignac number, because 77865603856555 - 2²⁵ = 77865570302123 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7786560385651 + ... + 7786560385660.

It is an arithmetic number, because the mean of its divisors is an integer number (23359681156968).

Almost surely, 2^{77865603856555} is an apocalyptic number.

77865603856555 is a deficient number, since it is larger than the sum of its proper divisors (15573120771317).

77865603856555 is a wasteful number, since it uses less digits than its factorization.

77865603856555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15573120771316.

The product of its (nonzero) digits is 6350400000, while the sum is 76.

The spelling of 77865603856555 in words is "seventy-seven trillion, eight hundred sixty-five billion, six hundred three million, eight hundred fifty-six thousand, five hundred fifty-five".