1291608389 has 2 divisors, whose sum is σ = 1291608390. Its totient is φ = 1291608388.

The previous prime is 1291608377. The next prime is 1291608421. The reversal of 1291608389 is 9838061921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 997485889 + 294122500 = 31583^2 + 17150^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1291608389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1291608349) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 645804194 + 645804195.

It is an arithmetic number, because the mean of its divisors is an integer number (645804195).

Almost surely, 2^1291608389 is an apocalyptic number.

It is an amenable number.

1291608389 is a deficient number, since it is larger than the sum of its proper divisors (1).

1291608389 is an equidigital number, since it uses as much as digits as its factorization.

1291608389 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 186624, while the sum is 47.

The square root of 1291608389 is about 35938.9536436441. The cubic root of 1291608389 is about 1089.0394671908.

The spelling of 1291608389 in words is "one billion, two hundred ninety-one million, six hundred eight thousand, three hundred eighty-nine".