77688556228 has 12 divisors (see below), whose sum is σ = 140643076140. Its totient is φ = 37504820192.

The previous prime is 77688556223. The next prime is 77688556259. The reversal of 77688556228 is 82265588677.

It can be written as a sum of positive squares in 2 ways, for example, as 51975792324 + 25712763904 = 227982^2 + 160352^2 .

It is a super-2 number, since 2×77688556228² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 77688556228.

It is not an unprimeable number, because it can be changed into a prime (77688556223) 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, 334864351 + ... + 334864582.

It is an arithmetic number, because the mean of its divisors is an integer number (11720256345).

Almost surely, 2^77688556228 is an apocalyptic number.

It is an amenable number.

77688556228 is a deficient number, since it is larger than the sum of its proper divisors (62954519912).

77688556228 is a wasteful number, since it uses less digits than its factorization.

77688556228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 669728966 (or 669728964 counting only the distinct ones).

The product of its digits is 90316800, while the sum is 64.

The spelling of 77688556228 in words is "seventy-seven billion, six hundred eighty-eight million, five hundred fifty-six thousand, two hundred twenty-eight".