1243361213 has 4 divisors (see below), whose sum is σ = 1247786268. Its totient is φ = 1238936160.

The previous prime is 1243361137. The next prime is 1243361257. The reversal of 1243361213 is 3121633421.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3121633421 = 1123 ⋅2779727.

It can be written as a sum of positive squares in 2 ways, for example, as 590149849 + 653211364 = 24293^2 + 25558^2 .

It is a cyclic number.

It is not a de Polignac number, because 1243361213 - 2¹⁰ = 1243360189 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 (1243361263) 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, 2212106 + ... + 2212667.

It is an arithmetic number, because the mean of its divisors is an integer number (311946567).

Almost surely, 2^1243361213 is an apocalyptic number.

It is an amenable number.

1243361213 is a deficient number, since it is larger than the sum of its proper divisors (4425055).

1243361213 is an equidigital number, since it uses as much as digits as its factorization.

1243361213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4425054.

The product of its digits is 2592, while the sum is 26.

The square root of 1243361213 is about 35261.3274423979. The cubic root of 1243361213 is about 1075.3069144943.

Adding to 1243361213 its reverse (3121633421), we get a palindrome (4364994634).

The spelling of 1243361213 in words is "one billion, two hundred forty-three million, three hundred sixty-one thousand, two hundred thirteen".