1243868139 has 12 divisors (see below), whose sum is σ = 1808144416. Its totient is φ = 823962672.

The previous prime is 1243868123. The next prime is 1243868147. The reversal of 1243868139 is 9318683421.

It is not a de Polignac number, because 1243868139 - 2⁴ = 1243868123 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1243868094 and 1243868103.

It is not an unprimeable number, because it can be changed into a prime (1243848139) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 438739 + ... + 441564.

Almost surely, 2^1243868139 is an apocalyptic number.

1243868139 is a deficient number, since it is larger than the sum of its proper divisors (564276277).

1243868139 is a wasteful number, since it uses less digits than its factorization.

1243868139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 880466 (or 880463 counting only the distinct ones).

The product of its digits is 248832, while the sum is 45.

The square root of 1243868139 is about 35268.5148397264. The cubic root of 1243868139 is about 1075.4530310488.

The spelling of 1243868139 in words is "one billion, two hundred forty-three million, eight hundred sixty-eight thousand, one hundred thirty-nine".