77688144 has 30 divisors (see below), whose sum is σ = 217419306. Its totient is φ = 25896000.

The previous prime is 77688137. The next prime is 77688157. The reversal of 77688144 is 44188677.

It can be written as a sum of positive squares in only one way, i.e., 64641600 + 13046544 = 8040^2 + 3612^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 77688144.

It is a congruent number.

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 269607 + ... + 269894.

Almost surely, 2^77688144 is an apocalyptic number.

It is an amenable number.

77688144 is an abundant number, since it is smaller than the sum of its proper divisors (139731162).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

77688144 is a wasteful number, since it uses less digits than its factorization.

77688144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 539515 (or 539506 counting only the distinct ones).

The product of its digits is 301056, while the sum is 45.

The square root of 77688144 is about 8814.0878144026. The cubic root of 77688144 is about 426.6956827055.

The spelling of 77688144 in words is "seventy-seven million, six hundred eighty-eight thousand, one hundred forty-four".