77851668517 has 8 divisors (see below), whose sum is σ = 91042483136. Its totient is φ = 65178140832.

The previous prime is 77851668511. The next prime is 77851668523. The reversal of 77851668517 is 71586615877.

It is an interprime number because it is at equal distance from previous prime (77851668511) and next prime (77851668523).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 77851668517 - 2²³ = 77843279909 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77851668511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 129321408 + ... + 129322009.

It is an arithmetic number, because the mean of its divisors is an integer number (11380310392).

Almost surely, 2^77851668517 is an apocalyptic number.

It is an amenable number.

77851668517 is a deficient number, since it is larger than the sum of its proper divisors (13190814619).

77851668517 is a wasteful number, since it uses less digits than its factorization.

77851668517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 258643467.

The product of its digits is 19756800, while the sum is 61.

The spelling of 77851668517 in words is "seventy-seven billion, eight hundred fifty-one million, six hundred sixty-eight thousand, five hundred seventeen".