9819820 has 12 divisors (see below), whose sum is σ = 20621664. Its totient is φ = 3927920.

The previous prime is 9819809. The next prime is 9819847. The reversal of 9819820 is 289189.

It is a self number, because there is not a number n which added to its sum of digits gives 9819820.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 245476 + ... + 245515.

It is an arithmetic number, because the mean of its divisors is an integer number (1718472).

Almost surely, 2^9819820 is an apocalyptic number.

It is an amenable number.

9819820 is an abundant number, since it is smaller than the sum of its proper divisors (10801844).

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

9819820 is a wasteful number, since it uses less digits than its factorization.

9819820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 491000 (or 490998 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 37.

The square root of 9819820 is about 3133.6592029128. The cubic root of 9819820 is about 214.1416653043.

It can be divided in two parts, 981 and 9820, that added together give a palindrome (10801).

The spelling of 9819820 in words is "nine million, eight hundred nineteen thousand, eight hundred twenty".