998966591 has 8 divisors (see below), whose sum is σ = 1201764480. Its totient is φ = 811190808.

The previous prime is 998966587. The next prime is 998966593. The reversal of 998966591 is 195669899.

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 998966591 - 2² = 998966587 is a prime.

It is a super-2 number, since 2×998966591² = 1995868499868322562, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (998966593) 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, 3755381 + ... + 3755646.

It is an arithmetic number, because the mean of its divisors is an integer number (150220560).

Almost surely, 2^998966591 is an apocalyptic number.

998966591 is a deficient number, since it is larger than the sum of its proper divisors (202797889).

998966591 is a wasteful number, since it uses less digits than its factorization.

998966591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7511053.

The product of its digits is 9447840, while the sum is 62.

The square root of 998966591 is about 31606.4327471482. The cubic root of 998966591 is about 999.6554116058.

The spelling of 998966591 in words is "nine hundred ninety-eight million, nine hundred sixty-six thousand, five hundred ninety-one".