9921398 has 16 divisors (see below), whose sum is σ = 15253920. Its totient is φ = 4838400.

The previous prime is 9921391. The next prime is 9921407. The reversal of 9921398 is 8931299.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9921391) 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, 15158 + ... + 15798.

It is an arithmetic number, because the mean of its divisors is an integer number (953370).

Almost surely, 2^9921398 is an apocalyptic number.

9921398 is a deficient number, since it is larger than the sum of its proper divisors (5332522).

9921398 is a wasteful number, since it uses less digits than its factorization.

9921398 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 823.

The product of its digits is 34992, while the sum is 41.

The square root of 9921398 is about 3149.8250745081. The cubic root of 9921398 is about 214.8775072937.

Subtracting from 9921398 its reverse (8931299), we obtain a palindrome (990099).

The spelling of 9921398 in words is "nine million, nine hundred twenty-one thousand, three hundred ninety-eight".