20111121123 has 4 divisors (see below), whose sum is σ = 26814828168. Its totient is φ = 13407414080.

The previous prime is 20111121103. The next prime is 20111121139. The reversal of 20111121123 is 32112111102.

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 20111121123 - 2⁹ = 20111120611 is a prime.

It is a super-2 number, since 2×20111121123² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20111121103) 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, 3351853518 + ... + 3351853523.

It is an arithmetic number, because the mean of its divisors is an integer number (6703707042).

Almost surely, 2^20111121123 is an apocalyptic number.

20111121123 is a deficient number, since it is larger than the sum of its proper divisors (6703707045).

20111121123 is an equidigital number, since it uses as much as digits as its factorization.

20111121123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6703707044.

The product of its (nonzero) digits is 24, while the sum is 15.

Adding to 20111121123 its reverse (32112111102), we get a palindrome (52223232225).

The spelling of 20111121123 in words is "twenty billion, one hundred eleven million, one hundred twenty-one thousand, one hundred twenty-three".