9381720820 has 48 divisors (see below), whose sum is σ = 20769134400. Its totient is φ = 3549934080.

The previous prime is 9381720773. The next prime is 9381720857. The reversal of 9381720820 is 280271839.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 244716 + ... + 280444.

It is an arithmetic number, because the mean of its divisors is an integer number (432690300).

Almost surely, 2^9381720820 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 9381720820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10384567200).

9381720820 is an abundant number, since it is smaller than the sum of its proper divisors (11387413580).

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

9381720820 is a wasteful number, since it uses less digits than its factorization.

9381720820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36448 (or 36446 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 40.

The square root of 9381720820 is about 96859.2836025541. The cubic root of 9381720820 is about 2109.0854148181.

The spelling of 9381720820 in words is "nine billion, three hundred eighty-one million, seven hundred twenty thousand, eight hundred twenty".