1278148643 has 2 divisors, whose sum is σ = 1278148644. Its totient is φ = 1278148642.

The previous prime is 1278148607. The next prime is 1278148657. The reversal of 1278148643 is 3468418721.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1278148643 - 2⁶ = 1278148579 is a prime.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 1278148594 and 1278148603.

It is not a weakly prime, because it can be changed into another prime (1278148673) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 639074321 + 639074322.

It is an arithmetic number, because the mean of its divisors is an integer number (639074322).

Almost surely, 2^1278148643 is an apocalyptic number.

1278148643 is a deficient number, since it is larger than the sum of its proper divisors (1).

1278148643 is an equidigital number, since it uses as much as digits as its factorization.

1278148643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 258048, while the sum is 44.

The square root of 1278148643 is about 35751.2047769023. The cubic root of 1278148643 is about 1085.2433194661.

The spelling of 1278148643 in words is "one billion, two hundred seventy-eight million, one hundred forty-eight thousand, six hundred forty-three".