9781020 has 96 divisors (see below), whose sum is σ = 31046400. Its totient is φ = 2555712.

The previous prime is 9781007. The next prime is 9781021. The reversal of 9781020 is 201879.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9781021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 31707 + ... + 32013.

It is an arithmetic number, because the mean of its divisors is an integer number (323400).

Almost surely, 2^9781020 is an apocalyptic number.

9781020 is a gapful number since it is divisible by the number (90) 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 9781020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15523200).

9781020 is an abundant number, since it is smaller than the sum of its proper divisors (21265380).

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

9781020 is a wasteful number, since it uses less digits than its factorization.

9781020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 384 (or 376 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 27.

The square root of 9781020 is about 3127.4622299878. The cubic root of 9781020 is about 213.8592547039.

Adding to 9781020 its reverse (201879), we get a palindrome (9982899).

The spelling of 9781020 in words is "nine million, seven hundred eighty-one thousand, twenty".