87777777777777 has 6 divisors (see below), whose sum is σ = 126790123456802. Its totient is φ = 58518518518512.

The previous prime is 87777777777763. The next prime is 87777777777847. The reversal of 87777777777777 is 77777777777778.

It can be written as a sum of positive squares in only one way, i.e., 82656626881761 + 5121150896016 = 9091569^2 + 2262996^2 .

It is not a de Polignac number, because 87777777777777 - 2¹⁰ = 87777777776753 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (87777777775777) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4876543209868 + ... + 4876543209885.

Almost surely, 2^{87777777777777} is an apocalyptic number.

It is an amenable number.

87777777777777 is a deficient number, since it is larger than the sum of its proper divisors (39012345679025).

87777777777777 is a wasteful number, since it uses less digits than its factorization.

87777777777777 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9753086419759 (or 9753086419756 counting only the distinct ones).

The product of its digits is 775112083256, while the sum is 99.

Subtracting from 87777777777777 its reverse (77777777777778), we obtain a palindrome (9999999999999).

The spelling of 87777777777777 in words is "eighty-seven trillion, seven hundred seventy-seven billion, seven hundred seventy-seven million, seven hundred seventy-seven thousand, seven hundred seventy-seven".