21211211022123 has 16 divisors (see below), whose sum is σ = 30143551942656. Its totient is φ = 13220856105600.

The previous prime is 21211211022061. The next prime is 21211211022143. The reversal of 21211211022123 is 32122011211212.

It is not a de Polignac number, because 21211211022123 - 2²⁶ = 21211143913259 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21211211022123.

It is not an unprimeable number, because it can be changed into a prime (21211211022143) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1377164811 + ... + 1377180212.

It is an arithmetic number, because the mean of its divisors is an integer number (1883971996416).

Almost surely, 2^{21211211022123} is an apocalyptic number.

21211211022123 is a deficient number, since it is larger than the sum of its proper divisors (8932340920533).

21211211022123 is a wasteful number, since it uses less digits than its factorization.

21211211022123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2754345194.

The product of its (nonzero) digits is 192, while the sum is 21.

Adding to 21211211022123 its reverse (32122011211212), we get a palindrome (53333222233335).

The spelling of 21211211022123 in words is "twenty-one trillion, two hundred eleven billion, two hundred eleven million, twenty-two thousand, one hundred twenty-three".