1315621213 has 4 divisors (see below), whose sum is σ = 1317768028. Its totient is φ = 1313474400.

The previous prime is 1315621201. The next prime is 1315621283. The reversal of 1315621213 is 3121265131.

It is a happy number.

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 69672409 + 1245948804 = 8347^2 + 35298^2 .

It is a cyclic number.

It is not a de Polignac number, because 1315621213 - 2¹³ = 1315613021 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 (1315621283) 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, 1072488 + ... + 1073713.

It is an arithmetic number, because the mean of its divisors is an integer number (329442007).

Almost surely, 2^1315621213 is an apocalyptic number.

It is an amenable number.

1315621213 is a deficient number, since it is larger than the sum of its proper divisors (2146815).

1315621213 is an equidigital number, since it uses as much as digits as its factorization.

1315621213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2146814.

The product of its digits is 1080, while the sum is 25.

The square root of 1315621213 is about 36271.4931178743. The cubic root of 1315621213 is about 1095.7469970846.

Adding to 1315621213 its reverse (3121265131), we get a palindrome (4436886344).

The spelling of 1315621213 in words is "one billion, three hundred fifteen million, six hundred twenty-one thousand, two hundred thirteen".