211221212112123 has 16 divisors (see below), whose sum is σ = 284420320751136. Its totient is φ = 139418158118400.

The previous prime is 211221212112091. The next prime is 211221212112143. The reversal of 211221212112123 is 321211212122112.

It is a happy number.

It is not a de Polignac number, because 211221212112123 - 2⁵ = 211221212112091 is a prime.

It is a super-2 number, since 2×211221212112123² (a number of 29 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 211221212112093 and 211221212112102.

It is not an unprimeable number, because it can be changed into a prime (211221212112143) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19472211 + ... + 28312707.

It is an arithmetic number, because the mean of its divisors is an integer number (17776270046946).

Almost surely, 2^{211221212112123} is an apocalyptic number.

211221212112123 is a deficient number, since it is larger than the sum of its proper divisors (73199108639013).

211221212112123 is a wasteful number, since it uses less digits than its factorization.

211221212112123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8919454.

The product of its digits is 384, while the sum is 24.

Adding to 211221212112123 its reverse (321211212122112), we get a palindrome (532432424234235).

The spelling of 211221212112123 in words is "two hundred eleven trillion, two hundred twenty-one billion, two hundred twelve million, one hundred twelve thousand, one hundred twenty-three".