1243768013 has 4 divisors (see below), whose sum is σ = 1267235388. Its totient is φ = 1220300640.

The previous prime is 1243768007. The next prime is 1243768039. The reversal of 1243768013 is 3108673421.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3108673421 = 7 ⋅444096203.

It can be written as a sum of positive squares in 2 ways, for example, as 899220169 + 344547844 = 29987^2 + 18562^2 .

It is a cyclic number.

It is not a de Polignac number, because 1243768013 - 2⁴ = 1243767997 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 (1243768073) 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, 11733608 + ... + 11733713.

It is an arithmetic number, because the mean of its divisors is an integer number (316808847).

Almost surely, 2^1243768013 is an apocalyptic number.

It is an amenable number.

1243768013 is a deficient number, since it is larger than the sum of its proper divisors (23467375).

1243768013 is an equidigital number, since it uses as much as digits as its factorization.

1243768013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23467374.

The product of its (nonzero) digits is 24192, while the sum is 35.

The square root of 1243768013 is about 35267.0953297830. The cubic root of 1243768013 is about 1075.4241738368.

The spelling of 1243768013 in words is "one billion, two hundred forty-three million, seven hundred sixty-eight thousand, thirteen".