9721806 has 32 divisors (see below), whose sum is σ = 20684160. Its totient is φ = 3037536.

The previous prime is 9721793. The next prime is 9721813. The reversal of 9721806 is 6081279.

It is a congruent number.

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 15 ways as a sum of consecutive naturals, for example, 11800 + ... + 12596.

It is an arithmetic number, because the mean of its divisors is an integer number (646380).

Almost surely, 2^9721806 is an apocalyptic number.

9721806 is an abundant number, since it is smaller than the sum of its proper divisors (10962354).

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

9721806 is a wasteful number, since it uses less digits than its factorization.

9721806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 928.

The product of its (nonzero) digits is 6048, while the sum is 33.

The square root of 9721806 is about 3117.9810775564. The cubic root of 9721806 is about 213.4268150420.

The spelling of 9721806 in words is "nine million, seven hundred twenty-one thousand, eight hundred six".