21201323312021 has 8 divisors (see below), whose sum is σ = 22465714774104. Its totient is φ = 19938849049600.

The previous prime is 21201323312011. The next prime is 21201323312027. The reversal of 21201323312021 is 12021332310212.

It can be written as a sum of positive squares in 4 ways, for example, as 712528444996 + 20488794867025 = 844114^2 + 4526455^2 .

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 21201323312021 - 2³⁰ = 21200249570197 is a prime.

It is a super-2 number, since 2×21201323312021² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21201323312027) 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, 479277140 + ... + 479321373.

It is an arithmetic number, because the mean of its divisors is an integer number (2808214346763).

Almost surely, 2^{21201323312021} is an apocalyptic number.

It is an amenable number.

21201323312021 is a deficient number, since it is larger than the sum of its proper divisors (1264391462083).

21201323312021 is a wasteful number, since it uses less digits than its factorization.

21201323312021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 958599831.

The product of its (nonzero) digits is 864, while the sum is 23.

Adding to 21201323312021 its reverse (12021332310212), we get a palindrome (33222655622233).

The spelling of 21201323312021 in words is "twenty-one trillion, two hundred one billion, three hundred twenty-three million, three hundred twelve thousand, twenty-one".