1998543 has 16 divisors (see below), whose sum is σ = 2765696. Its totient is φ = 1283040.

The previous prime is 1998541. The next prime is 1998559. The reversal of 1998543 is 3458991.

It is not a de Polignac number, because 1998543 - 2¹ = 1998541 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 (1998541) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12180 + ... + 12342.

It is an arithmetic number, because the mean of its divisors is an integer number (172856).

2^1998543 is an apocalyptic number.

1998543 is a deficient number, since it is larger than the sum of its proper divisors (767153).

1998543 is a wasteful number, since it uses less digits than its factorization.

1998543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 294.

The product of its digits is 38880, while the sum is 39.

The square root of 1998543 is about 1413.6983412313. The cubic root of 1998543 is about 125.9615024741.

The spelling of 1998543 in words is "one million, nine hundred ninety-eight thousand, five hundred forty-three".