123132320021 has 4 divisors (see below), whose sum is σ = 123141508044. Its totient is φ = 123123132000.

The previous prime is 123132320011. The next prime is 123132320053. The reversal of 123132320021 is 120023231321.

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

It can be written as a sum of positive squares in 2 ways, for example, as 80378487121 + 42753832900 = 283511^2 + 206770^2 .

It is a cyclic number.

It is not a de Polignac number, because 123132320021 - 2¹⁰ = 123132318997 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 123132319975 and 123132320002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123132320011) 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, 4573880 + ... + 4600721.

It is an arithmetic number, because the mean of its divisors is an integer number (30785377011).

Almost surely, 2^123132320021 is an apocalyptic number.

It is an amenable number.

123132320021 is a deficient number, since it is larger than the sum of its proper divisors (9188023).

123132320021 is an equidigital number, since it uses as much as digits as its factorization.

123132320021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9188022.

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

Adding to 123132320021 its reverse (120023231321), we get a palindrome (243155551342).

The spelling of 123132320021 in words is "one hundred twenty-three billion, one hundred thirty-two million, three hundred twenty thousand, twenty-one".