8720077428 has 18 divisors (see below), whose sum is σ = 22042418034. Its totient is φ = 2906692464.

The previous prime is 8720077409. The next prime is 8720077463. The reversal of 8720077428 is 8247700278.

It can be written as a sum of positive squares in only one way, i.e., 8342630244 + 377447184 = 91338^2 + 19428^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 121112151 + ... + 121112222.

Almost surely, 2^8720077428 is an apocalyptic number.

It is an amenable number.

8720077428 is an abundant number, since it is smaller than the sum of its proper divisors (13322340606).

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

8720077428 is a wasteful number, since it uses less digits than its factorization.

8720077428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242224383 (or 242224378 counting only the distinct ones).

The product of its (nonzero) digits is 351232, while the sum is 45.

The square root of 8720077428 is about 93381.3548198997. The cubic root of 8720077428 is about 2058.2910252078.

The spelling of 8720077428 in words is "eight billion, seven hundred twenty million, seventy-seven thousand, four hundred twenty-eight".