1998004549 has 4 divisors (see below), whose sum is σ = 2084874336. Its totient is φ = 1911134764.

The previous prime is 1998004537. The next prime is 1998004597. The reversal of 1998004549 is 9454008991.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 1998004549 - 2⁹ = 1998004037 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1998004049) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 43434859 + ... + 43434904.

It is an arithmetic number, because the mean of its divisors is an integer number (521218584).

Almost surely, 2^1998004549 is an apocalyptic number.

It is an amenable number.

1998004549 is a deficient number, since it is larger than the sum of its proper divisors (86869787).

1998004549 is an equidigital number, since it uses as much as digits as its factorization.

1998004549 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86869786.

The product of its (nonzero) digits is 466560, while the sum is 49.

The square root of 1998004549 is about 44699.0441620400. The cubic root of 1998004549 is about 1259.5018920093.

The spelling of 1998004549 in words is "one billion, nine hundred ninety-eight million, four thousand, five hundred forty-nine".