20043400 has 72 divisors (see below), whose sum is σ = 50546430. Its totient is φ = 7388160.

The previous prime is 20043343. The next prime is 20043403. The reversal of 20043400 is 434002.

It can be written as a sum of positive squares in 9 ways, for example, as 133956 + 19909444 = 366^2 + 4462^2 .

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20043403) 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 17 ways as a sum of consecutive naturals, for example, 33504 + ... + 34096.

Almost surely, 2^20043400 is an apocalyptic number.

20043400 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 20043400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25273215).

20043400 is an abundant number, since it is smaller than the sum of its proper divisors (30503030).

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

20043400 is a wasteful number, since it uses less digits than its factorization.

20043400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 635 (or 613 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 13.

The square root of 20043400 is about 4476.9855930079. The cubic root of 20043400 is about 271.6379626834.

Adding to 20043400 its reverse (434002), we get a palindrome (20477402).

The spelling of 20043400 in words is "twenty million, forty-three thousand, four hundred".