1291270243 has 2 divisors, whose sum is σ = 1291270244. Its totient is φ = 1291270242.

The previous prime is 1291270199. The next prime is 1291270261. The reversal of 1291270243 is 3420721921.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1291270243 - 2¹³ = 1291262051 is a prime.

It is not a weakly prime, because it can be changed into another prime (1291277243) 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, 645635121 + 645635122.

It is an arithmetic number, because the mean of its divisors is an integer number (645635122).

Almost surely, 2^1291270243 is an apocalyptic number.

1291270243 is a deficient number, since it is larger than the sum of its proper divisors (1).

1291270243 is an equidigital number, since it uses as much as digits as its factorization.

1291270243 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6048, while the sum is 31.

The square root of 1291270243 is about 35934.2488859862. The cubic root of 1291270243 is about 1088.9444212300.

The spelling of 1291270243 in words is "one billion, two hundred ninety-one million, two hundred seventy thousand, two hundred forty-three".