21120212011123 has 16 divisors (see below), whose sum is σ = 22667872896000. Its totient is φ = 19606966733952.

The previous prime is 21120212011109. The next prime is 21120212011133. The reversal of 21120212011123 is 32111021202112.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21120212011123 is a prime.

It is a super-2 number, since 2×21120212011123² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21120212011123.

It is not an unprimeable number, because it can be changed into a prime (21120212011133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6347943 + ... + 9084976.

It is an arithmetic number, because the mean of its divisors is an integer number (1416742056000).

Almost surely, 2^{21120212011123} is an apocalyptic number.

21120212011123 is a deficient number, since it is larger than the sum of its proper divisors (1547660884877).

21120212011123 is a wasteful number, since it uses less digits than its factorization.

21120212011123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15434034.

The product of its (nonzero) digits is 96, while the sum is 19.

Adding to 21120212011123 its reverse (32111021202112), we get a palindrome (53231233213235).

The spelling of 21120212011123 in words is "twenty-one trillion, one hundred twenty billion, two hundred twelve million, eleven thousand, one hundred twenty-three".