21002100211123 has 2 divisors, whose sum is σ = 21002100211124. Its totient is φ = 21002100211122.

The previous prime is 21002100211111. The next prime is 21002100211129. The reversal of 21002100211123 is 32111200120012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21002100211123 - 2⁵ = 21002100211091 is a prime.

It is a super-2 number, since 2×21002100211123² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21002100211097 and 21002100211106.

It is not a weakly prime, because it can be changed into another prime (21002100211129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10501050105561 + 10501050105562.

It is an arithmetic number, because the mean of its divisors is an integer number (10501050105562).

Almost surely, 2^{21002100211123} is an apocalyptic number.

21002100211123 is a deficient number, since it is larger than the sum of its proper divisors (1).

21002100211123 is an equidigital number, since it uses as much as digits as its factorization.

21002100211123 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 21002100211123 its reverse (32111200120012), we get a palindrome (53113300331135).

The spelling of 21002100211123 in words is "twenty-one trillion, two billion, one hundred million, two hundred eleven thousand, one hundred twenty-three".