1291751 has 4 divisors (see below), whose sum is σ = 1296192. Its totient is φ = 1287312.

The previous prime is 1291691. The next prime is 1291783. The reversal of 1291751 is 1571921.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1571921 = 13 ⋅120917.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1291751 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1291751.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221751) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1751 + ... + 2376.

It is an arithmetic number, because the mean of its divisors is an integer number (324048).

2^1291751 is an apocalyptic number.

1291751 is a deficient number, since it is larger than the sum of its proper divisors (4441).

1291751 is an equidigital number, since it uses as much as digits as its factorization.

1291751 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4440.

The product of its digits is 630, while the sum is 26.

The square root of 1291751 is about 1136.5522425300. The cubic root of 1291751 is about 108.9079547268.

The spelling of 1291751 in words is "one million, two hundred ninety-one thousand, seven hundred fifty-one".