8720545 has 8 divisors (see below), whose sum is σ = 10561320. Its totient is φ = 6912000.

The previous prime is 8720533. The next prime is 8720557. The reversal of 8720545 is 5450278.

It is an interprime number because it is at equal distance from previous prime (8720533) and next prime (8720557).

It can be written as a sum of positive squares in 4 ways, for example, as 2917264 + 5803281 = 1708^2 + 2409^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 8720545 - 2⁵ = 8720513 is a prime.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 7456 + ... + 8545.

It is an arithmetic number, because the mean of its divisors is an integer number (1320165).

Almost surely, 2^8720545 is an apocalyptic number.

It is an amenable number.

8720545 is a deficient number, since it is larger than the sum of its proper divisors (1840775).

8720545 is a wasteful number, since it uses less digits than its factorization.

8720545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16115.

The product of its (nonzero) digits is 11200, while the sum is 31.

The square root of 8720545 is about 2953.0568907490. The cubic root of 8720545 is about 205.8327813186.

It can be divided in two parts, 8720 and 545, that multiplied together give a square (4752400 = 2180²).

The spelling of 8720545 in words is "eight million, seven hundred twenty thousand, five hundred forty-five".