19400 has 24 divisors (see below), whose sum is σ = 45570. Its totient is φ = 7680.

The previous prime is 19391. The next prime is 19403. The reversal of 19400 is 491.

It can be written as a sum of positive squares in 3 ways, for example, as 13924 + 5476 = 118^2 + 74^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 152 + ... + 248.

2¹⁹⁴⁰⁰ is an apocalyptic number.

19400 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 19400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22785).

19400 is an abundant number, since it is smaller than the sum of its proper divisors (26170).

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

19400 is a wasteful number, since it uses less digits than its factorization.

19400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113 (or 104 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 14.

The square root of 19400 is about 139.2838827718. The cubic root of 19400 is about 26.8699738212.

Adding to 19400 its reverse (491), we get a palindrome (19891).

The spelling of 19400 in words is "nineteen thousand, four hundred".