21031222221001 has 2 divisors, whose sum is σ = 21031222221002. Its totient is φ = 21031222221000.

The previous prime is 21031222220951. The next prime is 21031222221049. The reversal of 21031222221001 is 10012222213012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19296867552400 + 1734354668601 = 4392820^2 + 1316949^2 .

It is a cyclic number.

It is not a de Polignac number, because 21031222221001 - 2²⁷ = 21031088003273 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21031222221001.

It is not a weakly prime, because it can be changed into another prime (21031222321001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10515611110500 + 10515611110501.

It is an arithmetic number, because the mean of its divisors is an integer number (10515611110501).

Almost surely, 2^{21031222221001} is an apocalyptic number.

It is an amenable number.

21031222221001 is a deficient number, since it is larger than the sum of its proper divisors (1).

21031222221001 is an equidigital number, since it uses as much as digits as its factorization.

21031222221001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 21031222221001 its reverse (10012222213012), we get a palindrome (31043444434013).

The spelling of 21031222221001 in words is "twenty-one trillion, thirty-one billion, two hundred twenty-two million, two hundred twenty-one thousand, one".