21230023123 has 8 divisors (see below), whose sum is σ = 21289086000. Its totient is φ = 21170995968.

The previous prime is 21230023033. The next prime is 21230023189. The reversal of 21230023123 is 32132003212.

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 21230023123 - 2¹³ = 21230014931 is a prime.

It is a super-2 number, since 2×21230023123² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21230023123.

It is not an unprimeable number, because it can be changed into a prime (21230023723) 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, 1548603 + ... + 1562251.

It is an arithmetic number, because the mean of its divisors is an integer number (2661135750).

Almost surely, 2^21230023123 is an apocalyptic number.

21230023123 is a deficient number, since it is larger than the sum of its proper divisors (59062877).

21230023123 is a wasteful number, since it uses less digits than its factorization.

21230023123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17861.

The product of its (nonzero) digits is 432, while the sum is 19.

Adding to 21230023123 its reverse (32132003212), we get a palindrome (53362026335).

The spelling of 21230023123 in words is "twenty-one billion, two hundred thirty million, twenty-three thousand, one hundred twenty-three".