1231345613 has 4 divisors (see below), whose sum is σ = 1231540128. Its totient is φ = 1231151100.

The previous prime is 1231345603. The next prime is 1231345627. The reversal of 1231345613 is 3165431321.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1231345613 - 2¹⁶ = 1231280077 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1231345603) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 87431 + ... + 100532.

It is an arithmetic number, because the mean of its divisors is an integer number (307885032).

Almost surely, 2^1231345613 is an apocalyptic number.

It is an amenable number.

1231345613 is a deficient number, since it is larger than the sum of its proper divisors (194515).

1231345613 is an equidigital number, since it uses as much as digits as its factorization.

1231345613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194514.

The product of its digits is 6480, while the sum is 29.

The square root of 1231345613 is about 35090.5345214347. The cubic root of 1231345613 is about 1071.8318441804.

Adding to 1231345613 its reverse (3165431321), we get a palindrome (4396776934).

The spelling of 1231345613 in words is "one billion, two hundred thirty-one million, three hundred forty-five thousand, six hundred thirteen".