21100213313123 has 48 divisors (see below), whose sum is σ = 26159696690400. Its totient is φ = 16910554752000.

The previous prime is 21100213313111. The next prime is 21100213313131. The reversal of 21100213313123 is 32131331200112.

It is not a de Polignac number, because 21100213313123 - 2¹² = 21100213309027 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21100213313173) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 81203573 + ... + 81463001.

It is an arithmetic number, because the mean of its divisors is an integer number (544993681050).

Almost surely, 2^{21100213313123} is an apocalyptic number.

21100213313123 is a deficient number, since it is larger than the sum of its proper divisors (5059483377277).

21100213313123 is a wasteful number, since it uses less digits than its factorization.

21100213313123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 260100 (or 260093 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 23.

Adding to 21100213313123 its reverse (32131331200112), we get a palindrome (53231544513235).

The spelling of 21100213313123 in words is "twenty-one trillion, one hundred billion, two hundred thirteen million, three hundred thirteen thousand, one hundred twenty-three".