1291278379 has 8 divisors (see below), whose sum is σ = 1316939472. Its totient is φ = 1265665440.

The previous prime is 1291278353. The next prime is 1291278383. The reversal of 1291278379 is 9738721921.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1291278379 - 2¹⁵ = 1291245611 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1291278179) 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 in 7 ways as a sum of consecutive naturals, for example, 44752 + ... + 67714.

It is an arithmetic number, because the mean of its divisors is an integer number (164617434).

Almost surely, 2^1291278379 is an apocalyptic number.

1291278379 is a deficient number, since it is larger than the sum of its proper divisors (25661093).

1291278379 is a wasteful number, since it uses less digits than its factorization.

1291278379 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24077.

The product of its digits is 381024, while the sum is 49.

The square root of 1291278379 is about 35934.3620925709. The cubic root of 1291278379 is about 1088.9467082888.

The spelling of 1291278379 in words is "one billion, two hundred ninety-one million, two hundred seventy-eight thousand, three hundred seventy-nine".