212121212123 has 2 divisors, whose sum is σ = 212121212124. Its totient is φ = 212121212122.

The previous prime is 212121212101. The next prime is 212121212159. The reversal of 212121212123 is 321212121212.

212121212123 is an esthetic number in base 10, because in such base its adjacent digits differ by 1.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 212121212123 - 2¹² = 212121208027 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a junction number, because it is equal to n+sod(n) for n = 212121212095 and 212121212104.

It is not a weakly prime, because it can be changed into another prime (212121212183) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106060606061 + 106060606062.

It is an arithmetic number, because the mean of its divisors is an integer number (106060606062).

Almost surely, 2^212121212123 is an apocalyptic number.

212121212123 is a deficient number, since it is larger than the sum of its proper divisors (1).

212121212123 is an equidigital number, since it uses as much as digits as its factorization.

212121212123 is an evil number, because the sum of its binary digits is even.

The product of its digits is 192, while the sum is 20.

Adding to 212121212123 its reverse (321212121212), we get a palindrome (533333333335).

It can be divided in two parts, 21212121212 and 3, that multiplied together give a palindrome (63636363636).

The spelling of 212121212123 in words is "two hundred twelve billion, one hundred twenty-one million, two hundred twelve thousand, one hundred twenty-three".