1998900 has 54 divisors (see below), whose sum is σ = 6268262. Its totient is φ = 532800.

The previous prime is 1998881. The next prime is 1998917. The reversal of 1998900 is 98991.

It can be written as a sum of positive squares in 3 ways, for example, as 224676 + 1774224 = 474^2 + 1332^2 .

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 211 + ... + 2010.

2^1998900 is an apocalyptic number.

1998900 is a gapful number since it is divisible by the number (10) 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 1998900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3134131).

1998900 is an abundant number, since it is smaller than the sum of its proper divisors (4269362).

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

1998900 is a wasteful number, since it uses less digits than its factorization.

1998900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2241 (or 2231 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 36.

The square root of 1998900 is about 1413.8246001538. The cubic root of 1998900 is about 125.9690022009.

The spelling of 1998900 in words is "one million, nine hundred ninety-eight thousand, nine hundred".