1281439979 has 2 divisors, whose sum is σ = 1281439980. Its totient is φ = 1281439978.

The previous prime is 1281439967. The next prime is 1281440051. The reversal of 1281439979 is 9799341821.

It is a weak prime.

It is an emirp because it is prime and its reverse (9799341821) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1281439979 - 2⁸ = 1281439723 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1281439979.

It is not a weakly prime, because it can be changed into another prime (1281439909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 640719989 + 640719990.

It is an arithmetic number, because the mean of its divisors is an integer number (640719990).

Almost surely, 2^1281439979 is an apocalyptic number.

1281439979 is a deficient number, since it is larger than the sum of its proper divisors (1).

1281439979 is an equidigital number, since it uses as much as digits as its factorization.

1281439979 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 979776, while the sum is 53.

The square root of 1281439979 is about 35797.2063016096. The cubic root of 1281439979 is about 1086.1740507565.

The spelling of 1281439979 in words is "one billion, two hundred eighty-one million, four hundred thirty-nine thousand, nine hundred seventy-nine".