1900 has 18 divisors (see below), whose sum is σ = 4340. Its totient is φ = 720.

The previous prime is 1889. The next prime is 1901. The reversal of 1900 is 91.

It is a happy number.

It is a super-2 number, since 2×1900² = 7220000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is an Ulam number.

1900 is an undulating number in base 7.

It is a plaindrome in base 6, base 11, base 12 and base 14.

It is a nialpdrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (1901) 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, 91 + ... + 109.

1900 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 1900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2170).

1900 is an abundant number, since it is smaller than the sum of its proper divisors (2440).

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

1900 is a wasteful number, since it uses less digits than its factorization.

1900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33 (or 26 counting only the distinct ones).

The product of its (nonzero) digits is 9, while the sum is 10.

The square root of 1900 is about 43.5889894354. The cubic root of 1900 is about 12.3856232963.

1900 divided by its sum of digits (10) gives a triangular number (190 = T₁₉).

Adding to 1900 its reverse (91), we get a palindrome (1991).

The spelling of 1900 in words is "one thousand, nine hundred".