1998438 has 16 divisors (see below), whose sum is σ = 4304496. Its totient is φ = 614880.

The previous prime is 1998431. The next prime is 1998443. The reversal of 1998438 is 8348991.

It is a self number, because there is not a number n which added to its sum of digits gives 1998438.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1998431) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12733 + ... + 12888.

It is an arithmetic number, because the mean of its divisors is an integer number (269031).

2^1998438 is an apocalyptic number.

1998438 is an abundant number, since it is smaller than the sum of its proper divisors (2306058).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1998438 is a wasteful number, since it uses less digits than its factorization.

1998438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25639.

The product of its digits is 62208, while the sum is 42.

The square root of 1998438 is about 1413.6612041080. The cubic root of 1998438 is about 125.9592965022.

The spelling of 1998438 in words is "one million, nine hundred ninety-eight thousand, four hundred thirty-eight".