21201000220021 has 8 divisors (see below), whose sum is σ = 21415062987360. Its totient is φ = 20987816561328.

The previous prime is 21201000219977. The next prime is 21201000220027. The reversal of 21201000220021 is 12002200010212.

It is a happy number.

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 21201000220021 - 2¹¹ = 21201000217973 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21201000219983 and 21201000220010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21201000220027) 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, 219728686 + ... + 219825151.

It is an arithmetic number, because the mean of its divisors is an integer number (2676882873420).

Almost surely, 2^{21201000220021} is an apocalyptic number.

It is an amenable number.

21201000220021 is a deficient number, since it is larger than the sum of its proper divisors (214062767339).

21201000220021 is a wasteful number, since it uses less digits than its factorization.

21201000220021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 439554323.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21201000220021 its reverse (12002200010212), we get a palindrome (33203200230233).

The spelling of 21201000220021 in words is "twenty-one trillion, two hundred one billion, two hundred twenty thousand, twenty-one".