21123302123 has 8 divisors (see below), whose sum is σ = 26335545600. Its totient is φ = 16459715880.

The previous prime is 21123302107. The next prime is 21123302191. The reversal of 21123302123 is 32120332112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21123302123 - 2⁴ = 21123302107 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21123302095 and 21123302104.

It is not an unprimeable number, because it can be changed into a prime (21123302423) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 137164223 + ... + 137164376.

It is an arithmetic number, because the mean of its divisors is an integer number (3291943200).

Almost surely, 2^21123302123 is an apocalyptic number.

21123302123 is a deficient number, since it is larger than the sum of its proper divisors (5212243477).

21123302123 is a wasteful number, since it uses less digits than its factorization.

21123302123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 274328617.

The product of its (nonzero) digits is 432, while the sum is 20.

Adding to 21123302123 its reverse (32120332112), we get a palindrome (53243634235).

The spelling of 21123302123 in words is "twenty-one billion, one hundred twenty-three million, three hundred two thousand, one hundred twenty-three".