1231304321 has 8 divisors (see below), whose sum is σ = 1351040040. Its totient is φ = 1115142912.

The previous prime is 1231304317. The next prime is 1231304353. The reversal of 1231304321 is 1234031321.

It can be written as a sum of positive squares in 4 ways, for example, as 3783025 + 1227521296 = 1945^2 + 35036^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1231304321 - 2² = 1231304317 is a prime.

It is a super-2 number, since 2×1231304321² = 3032220661826542082, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1231304293 and 1231304302.

It is not an unprimeable number, because it can be changed into a prime (1231304021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 892856 + ... + 894233.

It is an arithmetic number, because the mean of its divisors is an integer number (168880005).

Almost surely, 2^1231304321 is an apocalyptic number.

It is an amenable number.

1231304321 is a deficient number, since it is larger than the sum of its proper divisors (119735719).

1231304321 is a wasteful number, since it uses less digits than its factorization.

1231304321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1787155.

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

The square root of 1231304321 is about 35089.9461527088. The cubic root of 1231304321 is about 1071.8198630938.

Adding to 1231304321 its reverse (1234031321), we get a palindrome (2465335642).

The spelling of 1231304321 in words is "one billion, two hundred thirty-one million, three hundred four thousand, three hundred twenty-one".