9998921 has 8 divisors (see below), whose sum is σ = 10750080.
Its totient is φ = 9270288.
The previous prime is 9998903. The next prime is 9998929. The reversal of 9998921 is 1298999.
It is a sphenic number, since it is the product of 3 distinct primes.
It is a cyclic number.
It is not a de Polignac number, because 9998921 - 218 = 9736777 is a prime.
It is a Harshad number since it is a multiple of its sum of digits (47).
It is a Duffinian number.
It is not an unprimeable number, because it can be changed into a prime (9998929) 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, 4706 + ... + 6491.
It is an arithmetic number, because the mean of its divisors is an integer number (1343760).
Almost surely, 29998921 is an apocalyptic number.
It is an amenable number.
9998921 is a deficient number, since it is larger than the sum of its proper divisors (751159).
9998921 is a wasteful number, since it uses less digits than its factorization.
9998921 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 11263.
The product of its digits is 104976, while the sum is 47.
The square root of 9998921 is about 3162.1070506863.
The cubic root of 9998921 is about 215.4357199410.
The spelling of 9998921 in words is "nine million, nine hundred ninety-eight thousand, nine hundred twenty-one".