1291145385 has 16 divisors (see below), whose sum is σ = 2066664384. Its totient is φ = 688333632.

The previous prime is 1291145371. The next prime is 1291145389. The reversal of 1291145385 is 5835411921.

It is not a de Polignac number, because 1291145385 - 2¹⁴ = 1291129001 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1291145389) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24414 + ... + 56376.

It is an arithmetic number, because the mean of its divisors is an integer number (129166524).

Almost surely, 2^1291145385 is an apocalyptic number.

1291145385 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1291145385 is a deficient number, since it is larger than the sum of its proper divisors (775518999).

1291145385 is a wasteful number, since it uses less digits than its factorization.

1291145385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34664.

The product of its digits is 43200, while the sum is 39.

The square root of 1291145385 is about 35932.5115320374. The cubic root of 1291145385 is about 1088.9093219919.

The spelling of 1291145385 in words is "one billion, two hundred ninety-one million, one hundred forty-five thousand, three hundred eighty-five".