21010242123 has 48 divisors (see below), whose sum is σ = 34521221280. Its totient is φ = 12206702592.

The previous prime is 21010242091. The next prime is 21010242131. The reversal of 21010242123 is 32124201012.

It is a happy number.

21010242123 is a `hidden beast` number, since 210 + 10 + 2 + 421 + 23 = 666.

It is not a de Polignac number, because 21010242123 - 2⁵ = 21010242091 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21010242096 and 21010242105.

It is not an unprimeable number, because it can be changed into a prime (21010242173) 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, 635211 + ... + 667467.

It is an arithmetic number, because the mean of its divisors is an integer number (719192110).

Almost surely, 2^21010242123 is an apocalyptic number.

21010242123 is a deficient number, since it is larger than the sum of its proper divisors (13510979157).

21010242123 is a wasteful number, since it uses less digits than its factorization.

21010242123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32588 (or 32585 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 21010242123 its reverse (32124201012), we get a palindrome (53134443135).

The spelling of 21010242123 in words is "twenty-one billion, ten million, two hundred forty-two thousand, one hundred twenty-three".