21211222222123 has 2 divisors, whose sum is σ = 21211222222124. Its totient is φ = 21211222222122.

The previous prime is 21211222222103. The next prime is 21211222222139. The reversal of 21211222222123 is 32122222211212.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21211222222123 - 2¹³ = 21211222213931 is a prime.

It is not a weakly prime, because it can be changed into another prime (21211222222103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605611111061 + 10605611111062.

It is an arithmetic number, because the mean of its divisors is an integer number (10605611111062).

Almost surely, 2^{21211222222123} is an apocalyptic number.

21211222222123 is a deficient number, since it is larger than the sum of its proper divisors (1).

21211222222123 is an equidigital number, since it uses as much as digits as its factorization.

21211222222123 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1536, while the sum is 25.

Adding to 21211222222123 its reverse (32122222211212), we get a palindrome (53333444433335).

The spelling of 21211222222123 in words is "twenty-one trillion, two hundred eleven billion, two hundred twenty-two million, two hundred twenty-two thousand, one hundred twenty-three".