20404211 has 4 divisors (see below), whose sum is σ = 20414232. Its totient is φ = 20394192.

The previous prime is 20404187. The next prime is 20404213. The reversal of 20404211 is 11240402.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 11240402 = 2 ⋅5620201.

It is a cyclic number.

It is not a de Polignac number, because 20404211 - 2¹⁴ = 20387827 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20404213) 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 3 ways as a sum of consecutive naturals, for example, 746 + ... + 6431.

It is an arithmetic number, because the mean of its divisors is an integer number (5103558).

Almost surely, 2^20404211 is an apocalyptic number.

20404211 is a deficient number, since it is larger than the sum of its proper divisors (10021).

20404211 is an equidigital number, since it uses as much as digits as its factorization.

20404211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10020.

The product of its (nonzero) digits is 64, while the sum is 14.

The square root of 20404211 is about 4517.1020577357. The cubic root of 20404211 is about 273.2582411540.

Adding to 20404211 its reverse (11240402), we get a palindrome (31644613).

The spelling of 20404211 in words is "twenty million, four hundred four thousand, two hundred eleven".