20404284 has 48 divisors (see below), whose sum is σ = 52164000. Its totient is φ = 6178816.

The previous prime is 20404261. The next prime is 20404331. The reversal of 20404284 is 48240402.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 4192 + ... + 7640.

It is an arithmetic number, because the mean of its divisors is an integer number (1086750).

Almost surely, 2^20404284 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20404284, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26082000).

20404284 is an abundant number, since it is smaller than the sum of its proper divisors (31759716).

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

20404284 is a wasteful number, since it uses less digits than its factorization.

20404284 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3502 (or 3500 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 24.

The square root of 20404284 is about 4517.1101381304. The cubic root of 20404284 is about 273.2585670316.

Adding to 20404284 its reverse (48240402), we get a palindrome (68644686).

The spelling of 20404284 in words is "twenty million, four hundred four thousand, two hundred eighty-four".