998100561 has 4 divisors (see below), whose sum is σ = 1330800752. Its totient is φ = 665400372.

The previous prime is 998100547. The next prime is 998100589. The reversal of 998100561 is 165001899.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 165001899 = 3 ⋅55000633.

It is not a de Polignac number, because 998100561 - 2¹¹ = 998098513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (998100161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 166350091 + ... + 166350096.

It is an arithmetic number, because the mean of its divisors is an integer number (332700188).

Almost surely, 2^998100561 is an apocalyptic number.

It is an amenable number.

998100561 is a deficient number, since it is larger than the sum of its proper divisors (332700191).

998100561 is a wasteful number, since it uses less digits than its factorization.

998100561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 332700190.

The product of its (nonzero) digits is 19440, while the sum is 39.

The square root of 998100561 is about 31592.7295591881. The cubic root of 998100561 is about 999.3664523688.

The spelling of 998100561 in words is "nine hundred ninety-eight million, one hundred thousand, five hundred sixty-one".