8500720 has 40 divisors (see below), whose sum is σ = 20110320. Its totient is φ = 3340800.

The previous prime is 8500711. The next prime is 8500729. The reversal of 8500720 is 270058.

It is an interprime number because it is at equal distance from previous prime (8500711) and next prime (8500729).

It is a tau number, because it is divible by the number of its divisors (40).

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 8500691 and 8500700.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8500729) 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, 3820 + ... + 5620.

It is an arithmetic number, because the mean of its divisors is an integer number (502758).

Almost surely, 2^8500720 is an apocalyptic number.

8500720 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 8500720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10055160).

8500720 is an abundant number, since it is smaller than the sum of its proper divisors (11609600).

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

8500720 is a wasteful number, since it uses less digits than its factorization.

8500720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1873 (or 1867 counting only the distinct ones).

The product of its (nonzero) digits is 560, while the sum is 22.

The square root of 8500720 is about 2915.5994237892. The cubic root of 8500720 is about 204.0885172698.

Adding to 8500720 its reverse (270058), we get a palindrome (8770778).

The spelling of 8500720 in words is "eight million, five hundred thousand, seven hundred twenty".