77117784857 has 4 divisors (see below), whose sum is σ = 77628498816. Its totient is φ = 76607070900.

The previous prime is 77117784823. The next prime is 77117784859. The reversal of 77117784857 is 75848771177.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 75848771177 = 461 ⋅164530957.

It is a cyclic number.

It is not a de Polignac number, because 77117784857 - 2¹⁴ = 77117768473 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 77117784857.

It is not an unprimeable number, because it can be changed into a prime (77117784859) 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, 255356753 + ... + 255357054.

It is an arithmetic number, because the mean of its divisors is an integer number (19407124704).

Almost surely, 2^77117784857 is an apocalyptic number.

It is an amenable number.

77117784857 is a deficient number, since it is larger than the sum of its proper divisors (510713959).

77117784857 is a wasteful number, since it uses less digits than its factorization.

77117784857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 510713958.

The product of its digits is 21512960, while the sum is 62.

The spelling of 77117784857 in words is "seventy-seven billion, one hundred seventeen million, seven hundred eighty-four thousand, eight hundred fifty-seven".