1291305 has 16 divisors (see below), whose sum is σ = 2133504. Its totient is φ = 666240.

The previous prime is 1291271. The next prime is 1291313. The reversal of 1291305 is 5031921.

It is not a de Polignac number, because 1291305 - 2⁷ = 1291177 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 924 + ... + 1853.

It is an arithmetic number, because the mean of its divisors is an integer number (133344).

2^1291305 is an apocalyptic number.

1291305 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1291305 is a deficient number, since it is larger than the sum of its proper divisors (842199).

1291305 is a wasteful number, since it uses less digits than its factorization.

1291305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2816.

The product of its (nonzero) digits is 270, while the sum is 21.

The square root of 1291305 is about 1136.3560181563. The cubic root of 1291305 is about 108.8954191481.

It can be divided in two parts, 1291 and 305, that added together give a triangular number (1596 = T₅₆).

The spelling of 1291305 in words is "one million, two hundred ninety-one thousand, three hundred five".