20431104 has 72 divisors (see below), whose sum is σ = 55923840. Its totient is φ = 6617088.

The previous prime is 20431097. The next prime is 20431121. The reversal of 20431104 is 40113402.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28057 + ... + 28775.

It is an arithmetic number, because the mean of its divisors is an integer number (776720).

Almost surely, 2^20431104 is an apocalyptic number.

20431104 is a gapful number since it is divisible by the number (24) 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 20431104, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27961920).

20431104 is an abundant number, since it is smaller than the sum of its proper divisors (35492736).

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

20431104 is an equidigital number, since it uses as much as digits as its factorization.

20431104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 775 (or 761 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 20431104 is about 4520.0778754353. The cubic root of 20431104 is about 273.3782410185.

Adding to 20431104 its reverse (40113402), we get a palindrome (60544506).

The spelling of 20431104 in words is "twenty million, four hundred thirty-one thousand, one hundred four".