20431221103 has 4 divisors (see below), whose sum is σ = 21319535088. Its totient is φ = 19542907120.

The previous prime is 20431221073. The next prime is 20431221131. The reversal of 20431221103 is 30112213402.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20431221103 - 2⁵ = 20431221071 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20431221193) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 444156958 + ... + 444157003.

It is an arithmetic number, because the mean of its divisors is an integer number (5329883772).

Almost surely, 2^20431221103 is an apocalyptic number.

20431221103 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

20431221103 is a deficient number, since it is larger than the sum of its proper divisors (888313985).

20431221103 is an equidigital number, since it uses as much as digits as its factorization.

20431221103 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 888313984.

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 20431221103 its reverse (30112213402), we get a palindrome (50543434505).

The spelling of 20431221103 in words is "twenty billion, four hundred thirty-one million, two hundred twenty-one thousand, one hundred three".