77887678877 has 4 divisors (see below), whose sum is σ = 77898894300. Its totient is φ = 77876463456.

The previous prime is 77887678789. The next prime is 77887678903.

77887678877 is nontrivially palindromic in base 10.

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

It can be written as a sum of positive squares in 2 ways, for example, as 42686039236 + 35201639641 = 206606^2 + 187621^2 .

It is a cyclic number.

It is not a de Polignac number, because 77887678877 - 2⁸ = 77887678621 is a prime.

It is a super-2 number, since 2×77887678877² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77887678277) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5597288 + ... + 5611185.

It is an arithmetic number, because the mean of its divisors is an integer number (19474723575).

Almost surely, 2^77887678877 is an apocalyptic number.

It is an amenable number.

77887678877 is a deficient number, since it is larger than the sum of its proper divisors (11215423).

77887678877 is a wasteful number, since it uses less digits than its factorization.

77887678877 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11215422.

The product of its digits is 2891341824, while the sum is 80.

The spelling of 77887678877 in words is "seventy-seven billion, eight hundred eighty-seven million, six hundred seventy-eight thousand, eight hundred seventy-seven".