8720705 has 16 divisors (see below), whose sum is σ = 12031104. Its totient is φ = 5944320.

The previous prime is 8720693. The next prime is 8720707. The reversal of 8720705 is 5070278.

It is not a de Polignac number, because 8720705 - 2⁴ = 8720689 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8720707) 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 in 15 ways as a sum of consecutive naturals, for example, 6110 + ... + 7400.

It is an arithmetic number, because the mean of its divisors is an integer number (751944).

Almost surely, 2^8720705 is an apocalyptic number.

It is an amenable number.

8720705 is a deficient number, since it is larger than the sum of its proper divisors (3310399).

8720705 is a wasteful number, since it uses less digits than its factorization.

8720705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1496.

The product of its (nonzero) digits is 3920, while the sum is 29.

The square root of 8720705 is about 2953.0839811966. The cubic root of 8720705 is about 205.8340401483.

The spelling of 8720705 in words is "eight million, seven hundred twenty thousand, seven hundred five".