123530220505 has 4 divisors (see below), whose sum is σ = 148236264612. Its totient is φ = 98824176400.

The previous prime is 123530220491. The next prime is 123530220547. The reversal of 123530220505 is 505022035321.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 505022035321 = 667241 ⋅756881.

It can be written as a sum of positive squares in 2 ways, for example, as 76190904729 + 47339315776 = 276027^2 + 217576^2 .

It is not a de Polignac number, because 123530220505 - 2¹¹ = 123530218457 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12353022046 + ... + 12353022055.

It is an arithmetic number, because the mean of its divisors is an integer number (37059066153).

Almost surely, 2^123530220505 is an apocalyptic number.

It is an amenable number.

123530220505 is a deficient number, since it is larger than the sum of its proper divisors (24706044107).

123530220505 is an equidigital number, since it uses as much as digits as its factorization.

123530220505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24706044106.

The product of its (nonzero) digits is 9000, while the sum is 28.

Adding to 123530220505 its reverse (505022035321), we get a palindrome (628552255826).

It can be divided in two parts, 123530 and 220505, that added together give a triangular number (344035 = T₈₂₉).

The spelling of 123530220505 in words is "one hundred twenty-three billion, five hundred thirty million, two hundred twenty thousand, five hundred five".