20104656 has 160 divisors (see below), whose sum is σ = 63745920. Its totient is φ = 5376000.

The previous prime is 20104639. The next prime is 20104657. The reversal of 20104656 is 65640102.

It is a hoax number, since the sum of its digits (24) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20104657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 199006 + ... + 199106.

It is an arithmetic number, because the mean of its divisors is an integer number (398412).

Almost surely, 2^20104656 is an apocalyptic number.

20104656 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20104656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31872960).

20104656 is an abundant number, since it is smaller than the sum of its proper divisors (43641264).

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

20104656 is a wasteful number, since it uses less digits than its factorization.

20104656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165 (or 159 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 20104656 is about 4483.8215843184. The cubic root of 20104656 is about 271.9144050164.

Adding to 20104656 its reverse (65640102), we get a palindrome (85744758).

It can be divided in two parts, 201046 and 56, that added together give a palindrome (201102).

The spelling of 20104656 in words is "twenty million, one hundred four thousand, six hundred fifty-six".