21001331321333 has 4 divisors (see below), whose sum is σ = 22910543259648. Its totient is φ = 19092119383020.

The previous prime is 21001331321317. The next prime is 21001331321429. The reversal of 21001331321333 is 33312313310012.

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 21001331321333 - 2⁴ = 21001331321317 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001331321533) 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, 954605969141 + ... + 954605969162.

It is an arithmetic number, because the mean of its divisors is an integer number (5727635814912).

Almost surely, 2^{21001331321333} is an apocalyptic number.

It is an amenable number.

21001331321333 is a deficient number, since it is larger than the sum of its proper divisors (1909211938315).

21001331321333 is a wasteful number, since it uses less digits than its factorization.

21001331321333 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1909211938314.

The product of its (nonzero) digits is 2916, while the sum is 26.

Adding to 21001331321333 its reverse (33312313310012), we get a palindrome (54313644631345).

The spelling of 21001331321333 in words is "twenty-one trillion, one billion, three hundred thirty-one million, three hundred twenty-one thousand, three hundred thirty-three".