21331300021 has 8 divisors (see below), whose sum is σ = 22400527104. Its totient is φ = 20273887920.

The previous prime is 21331300013. The next prime is 21331300037. The reversal of 21331300021 is 12000313312.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21331300021 - 2³ = 21331300013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21331299968 and 21331300004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21331304021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2950045 + ... + 2957266.

It is an arithmetic number, because the mean of its divisors is an integer number (2800065888).

Almost surely, 2^21331300021 is an apocalyptic number.

It is an amenable number.

21331300021 is a deficient number, since it is larger than the sum of its proper divisors (1069227083).

21331300021 is a wasteful number, since it uses less digits than its factorization.

21331300021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5907491.

The product of its (nonzero) digits is 108, while the sum is 16.

Adding to 21331300021 its reverse (12000313312), we get a palindrome (33331613333).

The spelling of 21331300021 in words is "twenty-one billion, three hundred thirty-one million, three hundred thousand, twenty-one".