1998439445 has 16 divisors (see below), whose sum is σ = 2522880000. Its totient is φ = 1517452608.

The previous prime is 1998439439. The next prime is 1998439451. The reversal of 1998439445 is 5449348991.

It is an interprime number because it is at equal distance from previous prime (1998439439) and next prime (1998439451).

It is not a de Polignac number, because 1998439445 - 2²⁴ = 1981662229 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 108245 + ... + 125354.

It is an arithmetic number, because the mean of its divisors is an integer number (157680000).

Almost surely, 2^1998439445 is an apocalyptic number.

It is an amenable number.

1998439445 is a deficient number, since it is larger than the sum of its proper divisors (524440555).

1998439445 is a wasteful number, since it uses less digits than its factorization.

1998439445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233692.

The product of its digits is 5598720, while the sum is 56.

The square root of 1998439445 is about 44703.9086098744. The cubic root of 1998439445 is about 1259.5932686110.

The spelling of 1998439445 in words is "one billion, nine hundred ninety-eight million, four hundred thirty-nine thousand, four hundred forty-five".