998591549 has 2 divisors, whose sum is σ = 998591550. Its totient is φ = 998591548.

The previous prime is 998591519. The next prime is 998591567. The reversal of 998591549 is 945195899.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 968143225 + 30448324 = 31115^2 + 5518^2 .

It is an emirp because it is prime and its reverse (945195899) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 998591549 - 2²⁴ = 981814333 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (998591519) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499295774 + 499295775.

It is an arithmetic number, because the mean of its divisors is an integer number (499295775).

Almost surely, 2^998591549 is an apocalyptic number.

It is an amenable number.

998591549 is a deficient number, since it is larger than the sum of its proper divisors (1).

998591549 is an equidigital number, since it uses as much as digits as its factorization.

998591549 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5248800, while the sum is 59.

The square root of 998591549 is about 31600.4991890951. The cubic root of 998591549 is about 999.5302957458.

The spelling of 998591549 in words is "nine hundred ninety-eight million, five hundred ninety-one thousand, five hundred forty-nine".