1998432 has 72 divisors (see below), whose sum is σ = 5916456. Its totient is φ = 663552.

The previous prime is 1998431. The next prime is 1998443. The reversal of 1998432 is 2348991.

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is an Ulam number.

It is a zygodrome in base 2 and base 7.

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 11 ways as a sum of consecutive naturals, for example, 7648 + ... + 7904.

It is an arithmetic number, because the mean of its divisors is an integer number (82173).

2^1998432 is an apocalyptic number.

1998432 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1998432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2958228).

1998432 is an abundant number, since it is smaller than the sum of its proper divisors (3918024).

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

1998432 is an equidigital number, since it uses as much as digits as its factorization.

1998432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 282 (or 262 counting only the distinct ones).

The product of its digits is 15552, while the sum is 36.

The square root of 1998432 is about 1413.6590819572. The cubic root of 1998432 is about 125.9591704443.

The spelling of 1998432 in words is "one million, nine hundred ninety-eight thousand, four hundred thirty-two".