1243378275841 has 4 divisors (see below), whose sum is σ = 1339022758612. Its totient is φ = 1147733793072.

The previous prime is 1243378275791. The next prime is 1243378275889. The reversal of 1243378275841 is 1485728733421.

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 87376995216 + 1156001280625 = 295596^2 + 1075175^2 .

It is a cyclic number.

It is not a de Polignac number, because 1243378275841 - 2⁹ = 1243378275329 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1243318275841) 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, 47822241366 + ... + 47822241391.

It is an arithmetic number, because the mean of its divisors is an integer number (334755689653).

Almost surely, 2^{1243378275841} is an apocalyptic number.

It is an amenable number.

1243378275841 is a deficient number, since it is larger than the sum of its proper divisors (95644482771).

1243378275841 is an equidigital number, since it uses as much as digits as its factorization.

1243378275841 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95644482770.

The product of its digits is 9031680, while the sum is 55.

The spelling of 1243378275841 in words is "one trillion, two hundred forty-three billion, three hundred seventy-eight million, two hundred seventy-five thousand, eight hundred forty-one".