123405305 has 4 divisors (see below), whose sum is σ = 148086372. Its totient is φ = 98724240.

The previous prime is 123405299. The next prime is 123405311. The reversal of 123405305 is 503504321.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 503504321 = 359 ⋅1402519.

It is an interprime number because it is at equal distance from previous prime (123405299) and next prime (123405311).

It can be written as a sum of positive squares in 2 ways, for example, as 50183056 + 73222249 = 7084^2 + 8557^2 .

It is not a de Polignac number, because 123405305 - 2⁶ = 123405241 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, 12340526 + ... + 12340535.

It is an arithmetic number, because the mean of its divisors is an integer number (37021593).

Almost surely, 2^123405305 is an apocalyptic number.

It is an amenable number.

123405305 is a deficient number, since it is larger than the sum of its proper divisors (24681067).

123405305 is an equidigital number, since it uses as much as digits as its factorization.

123405305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24681066.

The product of its (nonzero) digits is 1800, while the sum is 23.

The square root of 123405305 is about 11108.7940389585. The cubic root of 123405305 is about 497.8646334014.

Adding to 123405305 its reverse (503504321), we get a palindrome (626909626).

The spelling of 123405305 in words is "one hundred twenty-three million, four hundred five thousand, three hundred five".