8720428 has 6 divisors (see below), whose sum is σ = 15260756. Its totient is φ = 4360212.

The previous prime is 8720417. The next prime is 8720429. The reversal of 8720428 is 8240278.

It is a self number, because there is not a number n which added to its sum of digits gives 8720428.

It is not an unprimeable number, because it can be changed into a prime (8720429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1090050 + ... + 1090057.

Almost surely, 2^8720428 is an apocalyptic number.

It is an amenable number.

8720428 is a deficient number, since it is larger than the sum of its proper divisors (6540328).

8720428 is a wasteful number, since it uses less digits than its factorization.

8720428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2180111 (or 2180109 counting only the distinct ones).

The product of its (nonzero) digits is 7168, while the sum is 31.

The square root of 8720428 is about 2953.0370807018. The cubic root of 8720428 is about 205.8318607896.

The spelling of 8720428 in words is "eight million, seven hundred twenty thousand, four hundred twenty-eight".