21211211011123 has 32 divisors (see below), whose sum is σ = 25445516774400. Its totient is φ = 17287391020416.

The previous prime is 21211211011093. The next prime is 21211211011139. The reversal of 21211211011123 is 32111011211212.

It is a cyclic number.

It is not a de Polignac number, because 21211211011123 - 2¹⁷ = 21211210880051 is a prime.

It is a super-2 number, since 2×21211211011123² (a number of 27 digits) contains 22 as substring.

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 21211211011123.

It is not an unprimeable number, because it can be changed into a prime (21211211011223) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 83707965 + ... + 83960977.

It is an arithmetic number, because the mean of its divisors is an integer number (795172399200).

Almost surely, 2^{21211211011123} is an apocalyptic number.

21211211011123 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

21211211011123 is a deficient number, since it is larger than the sum of its proper divisors (4234305763277).

21211211011123 is a wasteful number, since it uses less digits than its factorization.

21211211011123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 256131.

The product of its (nonzero) digits is 48, while the sum is 19.

Adding to 21211211011123 its reverse (32111011211212), we get a palindrome (53322222222335).

The spelling of 21211211011123 in words is "twenty-one trillion, two hundred eleven billion, two hundred eleven million, eleven thousand, one hundred twenty-three".