20420004 has 72 divisors (see below), whose sum is σ = 53893728. Its totient is φ = 5967360.

The previous prime is 20419981. The next prime is 20420011. The reversal of 20420004 is 40002402.

It is a Harshad number since it is a multiple of its sum of digits (12).

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 23 ways as a sum of consecutive naturals, for example, 180652 + ... + 180764.

It is an arithmetic number, because the mean of its divisors is an integer number (748524).

Almost surely, 2^20420004 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 20420004, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26946864).

20420004 is an abundant number, since it is smaller than the sum of its proper divisors (33473724).

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

20420004 is a wasteful number, since it uses less digits than its factorization.

20420004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 205 (or 166 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 12.

The square root of 20420004 is about 4518.8498536685. The cubic root of 20420004 is about 273.3287242266.

Adding to 20420004 its reverse (40002402), we get a palindrome (60422406).

It can be divided in two parts, 20 and 420004, that added together give a palindrome (420024).

The spelling of 20420004 in words is "twenty million, four hundred twenty thousand, four".