20321023123 has 4 divisors (see below), whose sum is σ = 20321758480. Its totient is φ = 20320287768.

The previous prime is 20321023109. The next prime is 20321023133. The reversal of 20321023123 is 32132012302.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20321023123 - 2⁹ = 20321022611 is a prime.

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 20321023123.

It is not an unprimeable number, because it can be changed into a prime (20321023133) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 324540 + ... + 382057.

It is an arithmetic number, because the mean of its divisors is an integer number (5080439620).

Almost surely, 2^20321023123 is an apocalyptic number.

20321023123 is a deficient number, since it is larger than the sum of its proper divisors (735357).

20321023123 is an equidigital number, since it uses as much as digits as its factorization.

20321023123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 735356.

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

Adding to 20321023123 its reverse (32132012302), we get a palindrome (52453035425).

The spelling of 20321023123 in words is "twenty billion, three hundred twenty-one million, twenty-three thousand, one hundred twenty-three".