1291761 has 8 divisors (see below), whose sum is σ = 1913760. Its totient is φ = 861156.

The previous prime is 1291691. The next prime is 1291783. The reversal of 1291761 is 1671921.

It is not a de Polignac number, because 1291761 - 2⁹ = 1291249 is a prime.

It is a super-2 number, since 2×1291761² = 3337292962242, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 47843 = 1291761 / (1 + 2 + 9 + 1 + 7 + 6 + 1).

It is not an unprimeable number, because it can be changed into a prime (1291861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23895 + ... + 23948.

It is an arithmetic number, because the mean of its divisors is an integer number (239220).

2^1291761 is an apocalyptic number.

It is an amenable number.

1291761 is a deficient number, since it is larger than the sum of its proper divisors (621999).

1291761 is an equidigital number, since it uses as much as digits as its factorization.

1291761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47852 (or 47846 counting only the distinct ones).

The product of its digits is 756, while the sum is 27.

The square root of 1291761 is about 1136.5566417913. The cubic root of 1291761 is about 108.9082357605.

The spelling of 1291761 in words is "one million, two hundred ninety-one thousand, seven hundred sixty-one".