1998542 has 32 divisors (see below), whose sum is σ = 3763200. Its totient is φ = 775008.

The previous prime is 1998541. The next prime is 1998559. The reversal of 1998542 is 2458991.

It is an Ulam number.

Its product of digits (25920) is a multiple of the sum of its prime divisors (240).

It is a junction number, because it is equal to n+sod(n) for n = 1998496 and 1998505.

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, 14309 + ... + 14447.

It is an arithmetic number, because the mean of its divisors is an integer number (117600).

2^1998542 is an apocalyptic number.

1998542 is a deficient number, since it is larger than the sum of its proper divisors (1764658).

1998542 is a wasteful number, since it uses less digits than its factorization.

1998542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 240.

The product of its digits is 25920, while the sum is 38.

The square root of 1998542 is about 1413.6979875490. The cubic root of 1998542 is about 125.9614814653.

The spelling of 1998542 in words is "one million, nine hundred ninety-eight thousand, five hundred forty-two".