1213505313 has 4 divisors (see below), whose sum is σ = 1618007088. Its totient is φ = 809003540.

The previous prime is 1213505303. The next prime is 1213505327. The reversal of 1213505313 is 3135053121.

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 1213505313 - 2⁸ = 1213505057 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1213505303) 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, 202250883 + ... + 202250888.

It is an arithmetic number, because the mean of its divisors is an integer number (404501772).

Almost surely, 2^1213505313 is an apocalyptic number.

It is an amenable number.

1213505313 is a deficient number, since it is larger than the sum of its proper divisors (404501775).

1213505313 is an equidigital number, since it uses as much as digits as its factorization.

1213505313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 404501774.

The product of its (nonzero) digits is 1350, while the sum is 24.

The square root of 1213505313 is about 34835.4031554107. The cubic root of 1213505313 is about 1066.6302445354.

Adding to 1213505313 its reverse (3135053121), we get a palindrome (4348558434).

The spelling of 1213505313 in words is "one billion, two hundred thirteen million, five hundred five thousand, three hundred thirteen".