77265813865 has 4 divisors (see below), whose sum is σ = 92718976644. Its totient is φ = 61812651088.

The previous prime is 77265813857. The next prime is 77265813871. The reversal of 77265813865 is 56831856277.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56831856277 = 7 ⋅8118836611.

It can be written as a sum of positive squares in 2 ways, for example, as 51515834841 + 25749979024 = 226971^2 + 160468^2 .

It is a cyclic number.

It is not a de Polignac number, because 77265813865 - 2³ = 77265813857 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, 7726581382 + ... + 7726581391.

It is an arithmetic number, because the mean of its divisors is an integer number (23179744161).

Almost surely, 2^77265813865 is an apocalyptic number.

It is an amenable number.

77265813865 is a deficient number, since it is larger than the sum of its proper divisors (15453162779).

77265813865 is a wasteful number, since it uses less digits than its factorization.

77265813865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15453162778.

The product of its digits is 16934400, while the sum is 58.

The spelling of 77265813865 in words is "seventy-seven billion, two hundred sixty-five million, eight hundred thirteen thousand, eight hundred sixty-five".