21000231222001 has 4 divisors (see below), whose sum is σ = 21186073976292. Its totient is φ = 20814388467712.

The previous prime is 21000231221999. The next prime is 21000231222029. The reversal of 21000231222001 is 10022213200012.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 151866090000 + 20848365132001 = 389700^2 + 4566001^2 .

It is a cyclic number.

It is not a de Polignac number, because 21000231222001 - 2¹ = 21000231221999 is a prime.

It is a super-2 number, since 2×21000231222001² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21000231222041) 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, 92921376976 + ... + 92921377201.

It is an arithmetic number, because the mean of its divisors is an integer number (5296518494073).

Almost surely, 2^{21000231222001} is an apocalyptic number.

It is an amenable number.

21000231222001 is a deficient number, since it is larger than the sum of its proper divisors (185842754291).

21000231222001 is a wasteful number, since it uses less digits than its factorization.

21000231222001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185842754290.

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 21000231222001 its reverse (10022213200012), we get a palindrome (31022444422013).

The spelling of 21000231222001 in words is "twenty-one trillion, two hundred thirty-one million, two hundred twenty-two thousand, one".