998591291 has 2 divisors, whose sum is σ = 998591292. Its totient is φ = 998591290.

The previous prime is 998591273. The next prime is 998591329. The reversal of 998591291 is 192195899.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 998591291 - 2¹⁰ = 998590267 is a prime.

It is a super-2 number, since 2×998591291² = 1994369132922093362, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (998591591) 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 as a sum of consecutive naturals, namely, 499295645 + 499295646.

It is an arithmetic number, because the mean of its divisors is an integer number (499295646).

Almost surely, 2^998591291 is an apocalyptic number.

998591291 is a deficient number, since it is larger than the sum of its proper divisors (1).

998591291 is an equidigital number, since it uses as much as digits as its factorization.

998591291 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 524880, while the sum is 53.

The square root of 998591291 is about 31600.4951068808. The cubic root of 998591291 is about 999.5302096649.

The spelling of 998591291 in words is "nine hundred ninety-eight million, five hundred ninety-one thousand, two hundred ninety-one".