21113104123 has 2 divisors, whose sum is σ = 21113104124. Its totient is φ = 21113104122.

The previous prime is 21113104109. The next prime is 21113104139. The reversal of 21113104123 is 32140131112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21113104123 - 2²⁵ = 21079549691 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21113104123.

It is not a weakly prime, because it can be changed into another prime (21113104153) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556552061 + 10556552062.

It is an arithmetic number, because the mean of its divisors is an integer number (10556552062).

Almost surely, 2^21113104123 is an apocalyptic number.

21113104123 is a deficient number, since it is larger than the sum of its proper divisors (1).

21113104123 is an equidigital number, since it uses as much as digits as its factorization.

21113104123 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 19.

Adding to 21113104123 its reverse (32140131112), we get a palindrome (53253235235).

The spelling of 21113104123 in words is "twenty-one billion, one hundred thirteen million, one hundred four thousand, one hundred twenty-three".