211231210123 has 4 divisors (see below), whose sum is σ = 211344716128. Its totient is φ = 211117704120.

The previous prime is 211231210097. The next prime is 211231210159. The reversal of 211231210123 is 321012132112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 211231210123 - 2⁹ = 211231209611 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 211231210123.

It is not an unprimeable number, because it can be changed into a prime (211231210523) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 56750211 + ... + 56753932.

It is an arithmetic number, because the mean of its divisors is an integer number (52836179032).

Almost surely, 2^211231210123 is an apocalyptic number.

211231210123 is a deficient number, since it is larger than the sum of its proper divisors (113506005).

211231210123 is a wasteful number, since it uses less digits than its factorization.

211231210123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113506004.

The product of its (nonzero) digits is 144, while the sum is 19.

Adding to 211231210123 its reverse (321012132112), we get a palindrome (532243342235).

The spelling of 211231210123 in words is "two hundred eleven billion, two hundred thirty-one million, two hundred ten thousand, one hundred twenty-three".