1311020213 has 4 divisors (see below), whose sum is σ = 1328979468. Its totient is φ = 1293060960.

The previous prime is 1311020201. The next prime is 1311020233. The reversal of 1311020213 is 3120201131.

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 553284484 + 757735729 = 23522^2 + 27527^2 .

It is a cyclic number.

It is not a de Polignac number, because 1311020213 - 2¹⁴ = 1311003829 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 (1311020233) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8979518 + ... + 8979663.

It is an arithmetic number, because the mean of its divisors is an integer number (332244867).

Almost surely, 2^1311020213 is an apocalyptic number.

It is an amenable number.

1311020213 is a deficient number, since it is larger than the sum of its proper divisors (17959255).

1311020213 is an equidigital number, since it uses as much as digits as its factorization.

1311020213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17959254.

The product of its (nonzero) digits is 36, while the sum is 14.

The square root of 1311020213 is about 36208.0131048363. The cubic root of 1311020213 is about 1094.4681536954.

Adding to 1311020213 its reverse (3120201131), we get a palindrome (4431221344).

The spelling of 1311020213 in words is "one billion, three hundred eleven million, twenty thousand, two hundred thirteen".