77147728 has 40 divisors (see below), whose sum is σ = 171239040. Its totient is φ = 32983680.

The previous prime is 77147713. The next prime is 77147729. The reversal of 77147728 is 82774177.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77147729) 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 7 ways as a sum of consecutive naturals, for example, 91533 + ... + 92371.

It is an arithmetic number, because the mean of its divisors is an integer number (4280976).

Almost surely, 2^77147728 is an apocalyptic number.

It is an amenable number.

77147728 is an abundant number, since it is smaller than the sum of its proper divisors (94091312).

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

77147728 is a wasteful number, since it uses less digits than its factorization.

77147728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1675 (or 1669 counting only the distinct ones).

The product of its digits is 153664, while the sum is 43.

The square root of 77147728 is about 8783.3779379007. The cubic root of 77147728 is about 425.7039829689.

The spelling of 77147728 in words is "seventy-seven million, one hundred forty-seven thousand, seven hundred twenty-eight".