9721898 has 16 divisors (see below), whose sum is σ = 15175680. Its totient is φ = 4666896.

The previous prime is 9721897. The next prime is 9721919. The reversal of 9721898 is 8981279.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (9721891) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5015 + ... + 6677.

It is an arithmetic number, because the mean of its divisors is an integer number (948480).

Almost surely, 2^9721898 is an apocalyptic number.

9721898 is a deficient number, since it is larger than the sum of its proper divisors (5453782).

9721898 is a wasteful number, since it uses less digits than its factorization.

9721898 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1781.

The product of its digits is 72576, while the sum is 44.

The square root of 9721898 is about 3117.9958306579. The cubic root of 9721898 is about 213.4274882779.

The spelling of 9721898 in words is "nine million, seven hundred twenty-one thousand, eight hundred ninety-eight".