210001111123 has 4 divisors (see below), whose sum is σ = 210020471568. Its totient is φ = 209981750680.

The previous prime is 210001111097. The next prime is 210001111157. The reversal of 210001111123 is 321111100012.

It is a happy number.

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 210001111123 - 2²⁹ = 209464240211 is a prime.

It is a super-2 number, since 2×210001111123² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (210001111193) 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, 9663943 + ... + 9685648.

It is an arithmetic number, because the mean of its divisors is an integer number (52505117892).

Almost surely, 2^210001111123 is an apocalyptic number.

210001111123 is a deficient number, since it is larger than the sum of its proper divisors (19360445).

210001111123 is a wasteful number, since it uses less digits than its factorization.

210001111123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19360444.

The product of its (nonzero) digits is 12, while the sum is 13.

Adding to 210001111123 its reverse (321111100012), we get a palindrome (531112211135).

The spelling of 210001111123 in words is "two hundred ten billion, one million, one hundred eleven thousand, one hundred twenty-three".