1231230505 has 4 divisors (see below), whose sum is σ = 1477476612. Its totient is φ = 984984400.

The previous prime is 1231230437. The next prime is 1231230509. The reversal of 1231230505 is 5050321321.

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 157226521 + 1074003984 = 12539^2 + 32772^2 .

It is a de Polignac number, because none of the positive numbers 2^k-1231230505 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1231230509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 123123046 + ... + 123123055.

It is an arithmetic number, because the mean of its divisors is an integer number (369369153).

Almost surely, 2^1231230505 is an apocalyptic number.

It is an amenable number.

1231230505 is a deficient number, since it is larger than the sum of its proper divisors (246246107).

1231230505 is an equidigital number, since it uses as much as digits as its factorization.

1231230505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 246246106.

The product of its (nonzero) digits is 900, while the sum is 22.

The square root of 1231230505 is about 35088.8943256980. The cubic root of 1231230505 is about 1071.7984443336.

Adding to 1231230505 its reverse (5050321321), we get a palindrome (6281551826).

The spelling of 1231230505 in words is "one billion, two hundred thirty-one million, two hundred thirty thousand, five hundred five".