21421423203 has 4 divisors (see below), whose sum is σ = 28561897608. Its totient is φ = 14280948800.

The previous prime is 21421423201. The next prime is 21421423211. The reversal of 21421423203 is 30232412412.

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 21421423203 - 2¹ = 21421423201 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21421423201) 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, 3570237198 + ... + 3570237203.

It is an arithmetic number, because the mean of its divisors is an integer number (7140474402).

Almost surely, 2^21421423203 is an apocalyptic number.

21421423203 is a deficient number, since it is larger than the sum of its proper divisors (7140474405).

21421423203 is an equidigital number, since it uses as much as digits as its factorization.

21421423203 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7140474404.

The product of its (nonzero) digits is 2304, while the sum is 24.

Adding to 21421423203 its reverse (30232412412), we get a palindrome (51653835615).

The spelling of 21421423203 in words is "twenty-one billion, four hundred twenty-one million, four hundred twenty-three thousand, two hundred three".