21332400001221 has 64 divisors (see below), whose sum is σ = 29972064890880. Its totient is φ = 13470074196480.

The previous prime is 21332400001193. The next prime is 21332400001229. The reversal of 21332400001221 is 12210000423312.

It is a de Polignac number, because none of the positive numbers 2^k-21332400001221 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21332400001229) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3429091891 + ... + 3429098111.

It is an arithmetic number, because the mean of its divisors is an integer number (468313513920).

Almost surely, 2^{21332400001221} is an apocalyptic number.

It is an amenable number.

21332400001221 is a deficient number, since it is larger than the sum of its proper divisors (8639664889659).

21332400001221 is a wasteful number, since it uses less digits than its factorization.

21332400001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7506.

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 21332400001221 its reverse (12210000423312), we get a palindrome (33542400424533).

The spelling of 21332400001221 in words is "twenty-one trillion, three hundred thirty-two billion, four hundred million, one thousand, two hundred twenty-one".