21303423123 has 32 divisors (see below), whose sum is σ = 29066688000. Its totient is φ = 13875456000.

The previous prime is 21303423109. The next prime is 21303423131. The reversal of 21303423123 is 32132430312.

It is not a de Polignac number, because 21303423123 - 2⁶ = 21303423059 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21303423093 and 21303423102.

It is not an unprimeable number, because it can be changed into a prime (21303323123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13305523 + ... + 13307123.

It is an arithmetic number, because the mean of its divisors is an integer number (908334000).

Almost surely, 2^21303423123 is an apocalyptic number.

21303423123 is a deficient number, since it is larger than the sum of its proper divisors (7763264877).

21303423123 is a wasteful number, since it uses less digits than its factorization.

21303423123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2203.

The product of its (nonzero) digits is 2592, while the sum is 24.

Adding to 21303423123 its reverse (32132430312), we get a palindrome (53435853435).

The spelling of 21303423123 in words is "twenty-one billion, three hundred three million, four hundred twenty-three thousand, one hundred twenty-three".