21021001100123 has 2 divisors, whose sum is σ = 21021001100124. Its totient is φ = 21021001100122.

The previous prime is 21021001099979. The next prime is 21021001100137. The reversal of 21021001100123 is 32100110012012.

It is an a-pointer prime, because the next prime (21021001100137) can be obtained adding 21021001100123 to its sum of digits (14).

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21021001100123 - 2²⁸ = 21020732664667 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21021001100098 and 21021001100107.

It is not a weakly prime, because it can be changed into another prime (21021001100423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510500550061 + 10510500550062.

It is an arithmetic number, because the mean of its divisors is an integer number (10510500550062).

Almost surely, 2^{21021001100123} is an apocalyptic number.

21021001100123 is a deficient number, since it is larger than the sum of its proper divisors (1).

21021001100123 is an equidigital number, since it uses as much as digits as its factorization.

21021001100123 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24, while the sum is 14.

Adding to 21021001100123 its reverse (32100110012012), we get a palindrome (53121111112135).

The spelling of 21021001100123 in words is "twenty-one trillion, twenty-one billion, one million, one hundred thousand, one hundred twenty-three".