20394400 has 144 divisors (see below), whose sum is σ = 56105784. Its totient is φ = 7188480.

The previous prime is 20394389. The next prime is 20394401. The reversal of 20394400 is 449302.

It can be written as a sum of positive squares in 12 ways, for example, as 3055504 + 17338896 = 1748^2 + 4164^2 .

It is not an unprimeable number, because it can be changed into a prime (20394401) 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, 384774 + ... + 384826.

Almost surely, 2^20394400 is an apocalyptic number.

20394400 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 20394400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28052892).

20394400 is an abundant number, since it is smaller than the sum of its proper divisors (35711384).

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

20394400 is a wasteful number, since it uses less digits than its factorization.

20394400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123 (or 110 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 22.

The square root of 20394400 is about 4516.0159432845. The cubic root of 20394400 is about 273.2144370195.

The spelling of 20394400 in words is "twenty million, three hundred ninety-four thousand, four hundred".