20430400 has 63 divisors (see below), whose sum is σ = 50720371. Its totient is φ = 8099840.

The previous prime is 20430373. The next prime is 20430409. The reversal of 20430400 is 403402.

The square root of 20430400 is 4520.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 10394176 + 10036224 = 3224^2 + 3168^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20430409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 180744 + ... + 180856.

Almost surely, 2^20430400 is an apocalyptic number.

20430400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

20430400 is the 4520-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20430400

20430400 is an abundant number, since it is smaller than the sum of its proper divisors (30289971).

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

20430400 is an equidigital number, since it uses as much as digits as its factorization.

20430400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 248 (or 120 counting only the distinct ones).

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

The cubic root of 20430400 is about 273.3751010268.

Adding to 20430400 its reverse (403402), we get a palindrome (20833802).

The spelling of 20430400 in words is "twenty million, four hundred thirty thousand, four hundred".