1989400 has 96 divisors (see below), whose sum is σ = 5580000. Its totient is φ = 658560.

The previous prime is 1989353. The next prime is 1989401. The reversal of 1989400 is 49891.

1989400 = 270² + 271² + ... + 294².

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1989401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 68586 + ... + 68614.

It is an arithmetic number, because the mean of its divisors is an integer number (58125).

2^1989400 is an apocalyptic number.

1989400 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 1989400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2790000).

1989400 is an abundant number, since it is smaller than the sum of its proper divisors (3590600).

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

1989400 is a wasteful number, since it uses less digits than its factorization.

1989400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66 (or 43 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 31.

The square root of 1989400 is about 1410.4609175727. The cubic root of 1989400 is about 125.7691245400.

The spelling of 1989400 in words is "one million, nine hundred eighty-nine thousand, four hundred".