21303112021 has 4 divisors (see below), whose sum is σ = 21422124000. Its totient is φ = 21184100044.

The previous prime is 21303112013. The next prime is 21303112121. The reversal of 21303112021 is 12021130312.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21303112021 - 2³ = 21303112013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21303111986 and 21303112004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21303112121) 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, 59505721 + ... + 59506078.

It is an arithmetic number, because the mean of its divisors is an integer number (5355531000).

Almost surely, 2^21303112021 is an apocalyptic number.

It is an amenable number.

21303112021 is a deficient number, since it is larger than the sum of its proper divisors (119011979).

21303112021 is a wasteful number, since it uses less digits than its factorization.

21303112021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 119011978.

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 21303112021 its reverse (12021130312), we get a palindrome (33324242333).

The spelling of 21303112021 in words is "twenty-one billion, three hundred three million, one hundred twelve thousand, twenty-one".