21231232203 has 4 divisors (see below), whose sum is σ = 28308309608. Its totient is φ = 14154154800.

The previous prime is 21231232201. The next prime is 21231232213. The reversal of 21231232203 is 30223213212.

It is a happy number.

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

It is not a de Polignac number, because 21231232203 - 2¹ = 21231232201 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21231232203.

It is not an unprimeable number, because it can be changed into a prime (21231232201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3538538698 + ... + 3538538703.

It is an arithmetic number, because the mean of its divisors is an integer number (7077077402).

Almost surely, 2^21231232203 is an apocalyptic number.

21231232203 is a deficient number, since it is larger than the sum of its proper divisors (7077077405).

21231232203 is an equidigital number, since it uses as much as digits as its factorization.

21231232203 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7077077404.

The product of its (nonzero) digits is 864, while the sum is 21.

Adding to 21231232203 its reverse (30223213212), we get a palindrome (51454445415).

The spelling of 21231232203 in words is "twenty-one billion, two hundred thirty-one million, two hundred thirty-two thousand, two hundred three".