9720820 has 12 divisors (see below), whose sum is σ = 20413764. Its totient is φ = 3888320.

The previous prime is 9720817. The next prime is 9720827. The reversal of 9720820 is 280279.

9720820 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 2202256 + 7518564 = 1484^2 + 2742^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9720827) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 243001 + ... + 243040.

It is an arithmetic number, because the mean of its divisors is an integer number (1701147).

Almost surely, 2^9720820 is an apocalyptic number.

It is an amenable number.

9720820 is an abundant number, since it is smaller than the sum of its proper divisors (10692944).

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

9720820 is a wasteful number, since it uses less digits than its factorization.

9720820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 486050 (or 486048 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 28.

The square root of 9720820 is about 3117.8229584118. The cubic root of 9720820 is about 213.4195994433.

The spelling of 9720820 in words is "nine million, seven hundred twenty thousand, eight hundred twenty".