998996521 has 8 divisors (see below), whose sum is σ = 1006544000. Its totient is φ = 991461600.

The previous prime is 998996507. The next prime is 998996527. The reversal of 998996521 is 125699899.

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 998996521 - 2¹⁵ = 998963753 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (998996527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 208885 + ... + 213613.

It is an arithmetic number, because the mean of its divisors is an integer number (125818000).

Almost surely, 2^998996521 is an apocalyptic number.

It is an amenable number.

998996521 is a deficient number, since it is larger than the sum of its proper divisors (7547479).

998996521 is a wasteful number, since it uses less digits than its factorization.

998996521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6279.

The product of its digits is 3149280, while the sum is 58.

The square root of 998996521 is about 31606.9062231658. The cubic root of 998996521 is about 999.6653950520.

The spelling of 998996521 in words is "nine hundred ninety-eight million, nine hundred ninety-six thousand, five hundred twenty-one".