1278542839 has 12 divisors (see below), whose sum is σ = 1498645368. Its totient is φ = 1087522800.

The previous prime is 1278542831. The next prime is 1278542849. The reversal of 1278542839 is 9382458721.

It is not a de Polignac number, because 1278542839 - 2³ = 1278542831 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1278542792 and 1278542801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1278542831) 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, 93172 + ... + 106009.

It is an arithmetic number, because the mean of its divisors is an integer number (124887114).

Almost surely, 2^1278542839 is an apocalyptic number.

1278542839 is a deficient number, since it is larger than the sum of its proper divisors (220102529).

1278542839 is a wasteful number, since it uses less digits than its factorization.

1278542839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199326 (or 199319 counting only the distinct ones).

The product of its digits is 967680, while the sum is 49.

The square root of 1278542839 is about 35756.7173968752. The cubic root of 1278542839 is about 1085.3548752454.

The spelling of 1278542839 in words is "one billion, two hundred seventy-eight million, five hundred forty-two thousand, eight hundred thirty-nine".