20405230 has 16 divisors (see below), whose sum is σ = 36795024. Its totient is φ = 8147520.

The previous prime is 20405213. The next prime is 20405233. The reversal of 20405230 is 3250402.

It is a super-2 number, since 2×20405230² = 832746822705800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20405233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5434 + ... + 8386.

It is an arithmetic number, because the mean of its divisors is an integer number (2299689).

Almost surely, 2^20405230 is an apocalyptic number.

20405230 is a deficient number, since it is larger than the sum of its proper divisors (16389794).

20405230 is a wasteful number, since it uses less digits than its factorization.

20405230 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3651.

The product of its (nonzero) digits is 240, while the sum is 16.

The square root of 20405230 is about 4517.2148498826. The cubic root of 20405230 is about 273.2627899783.

Adding to 20405230 its reverse (3250402), we get a palindrome (23655632).

The spelling of 20405230 in words is "twenty million, four hundred five thousand, two hundred thirty".