77878628 has 12 divisors (see below), whose sum is σ = 136859520. Its totient is φ = 38775912.

The previous prime is 77878627. The next prime is 77878679. The reversal of 77878628 is 82687877.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 77878628.

It is not an unprimeable number, because it can be changed into a prime (77878627) 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 3 ways as a sum of consecutive naturals, for example, 39776 + ... + 41687.

It is an arithmetic number, because the mean of its divisors is an integer number (11404960).

Almost surely, 2^77878628 is an apocalyptic number.

It is an amenable number.

77878628 is a deficient number, since it is larger than the sum of its proper divisors (58980892).

77878628 is a wasteful number, since it uses less digits than its factorization.

77878628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81706 (or 81704 counting only the distinct ones).

The product of its digits is 2107392, while the sum is 53.

The square root of 77878628 is about 8824.8868547988. The cubic root of 77878628 is about 427.0441372545.

Subtracting 77878628 from its reverse (82687877), we obtain a square (4809249 = 2193²).

The spelling of 77878628 in words is "seventy-seven million, eight hundred seventy-eight thousand, six hundred twenty-eight".