1289431879 has 2 divisors, whose sum is σ = 1289431880. Its totient is φ = 1289431878.

The previous prime is 1289431867. The next prime is 1289431909. The reversal of 1289431879 is 9781349821.

It is a weak prime.

It is an emirp because it is prime and its reverse (9781349821) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1289431879 - 2¹⁹ = 1288907591 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1289431579) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 644715939 + 644715940.

It is an arithmetic number, because the mean of its divisors is an integer number (644715940).

Almost surely, 2^1289431879 is an apocalyptic number.

1289431879 is a deficient number, since it is larger than the sum of its proper divisors (1).

1289431879 is an equidigital number, since it uses as much as digits as its factorization.

1289431879 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 870912, while the sum is 52.

The square root of 1289431879 is about 35908.6602228487. The cubic root of 1289431879 is about 1088.4274039751.

The spelling of 1289431879 in words is "one billion, two hundred eighty-nine million, four hundred thirty-one thousand, eight hundred seventy-nine".