1291478473 has 2 divisors, whose sum is σ = 1291478474. Its totient is φ = 1291478472.

The previous prime is 1291478471. The next prime is 1291478477. The reversal of 1291478473 is 3748741921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1287589689 + 3888784 = 35883^2 + 1972^2 .

It is a cyclic number.

It is not a de Polignac number, because 1291478473 - 2¹ = 1291478471 is a prime.

Together with 1291478471, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1291478471) 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, 645739236 + 645739237.

It is an arithmetic number, because the mean of its divisors is an integer number (645739237).

Almost surely, 2^1291478473 is an apocalyptic number.

It is an amenable number.

1291478473 is a deficient number, since it is larger than the sum of its proper divisors (1).

1291478473 is an equidigital number, since it uses as much as digits as its factorization.

1291478473 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 338688, while the sum is 46.

The square root of 1291478473 is about 35937.1461443449. The cubic root of 1291478473 is about 1089.0029524090.

The spelling of 1291478473 in words is "one billion, two hundred ninety-one million, four hundred seventy-eight thousand, four hundred seventy-three".