21210120111001 has 2 divisors, whose sum is σ = 21210120111002. Its totient is φ = 21210120111000.

The previous prime is 21210120110951. The next prime is 21210120111013. The reversal of 21210120111001 is 10011102101212.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14703973099776 + 6506147011225 = 3834576^2 + 2550715^2 .

It is a cyclic number.

It is not a de Polignac number, because 21210120111001 - 2¹⁷ = 21210119979929 is a prime.

It is a super-2 number, since 2×21210120111001² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21210120111701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605060055500 + 10605060055501.

It is an arithmetic number, because the mean of its divisors is an integer number (10605060055501).

Almost surely, 2^{21210120111001} is an apocalyptic number.

It is an amenable number.

21210120111001 is a deficient number, since it is larger than the sum of its proper divisors (1).

21210120111001 is an equidigital number, since it uses as much as digits as its factorization.

21210120111001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 21210120111001 its reverse (10011102101212), we get a palindrome (31221222212213).

The spelling of 21210120111001 in words is "twenty-one trillion, two hundred ten billion, one hundred twenty million, one hundred eleven thousand, one".