2100400 has 60 divisors (see below), whose sum is σ = 5189400. Its totient is φ = 816640.

The previous prime is 2100377. The next prime is 2100403. The reversal of 2100400 is 40012.

It is not an unprimeable number, because it can be changed into a prime (2100403) 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, 23556 + ... + 23644.

It is an arithmetic number, because the mean of its divisors is an integer number (86490).

2^2100400 is an apocalyptic number.

2100400 is a gapful number since it is divisible by the number (20) 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 2100400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2594700).

2100400 is an abundant number, since it is smaller than the sum of its proper divisors (3089000).

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

2100400 is a wasteful number, since it uses less digits than its factorization.

2100400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166 (or 155 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 7.

The square root of 2100400 is about 1449.2756811594. The cubic root of 2100400 is about 128.0660466439.

Adding to 2100400 its reverse (40012), we get a palindrome (2140412).

It can be divided in two parts, 2100 and 400, that added together give a square (2500 = 50²).

The spelling of 2100400 in words is "two million, one hundred thousand, four hundred".