1280591 has 4 divisors (see below), whose sum is σ = 1379112. Its totient is φ = 1182072.

The previous prime is 1280567. The next prime is 1280597. The reversal of 1280591 is 1950821.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1950821 = 41 ⋅47581.

It is a cyclic number.

It is not a de Polignac number, because 1280591 - 2¹⁸ = 1018447 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 1280591.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1280597) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49241 + ... + 49266.

It is an arithmetic number, because the mean of its divisors is an integer number (344778).

2^1280591 is an apocalyptic number.

1280591 is a deficient number, since it is larger than the sum of its proper divisors (98521).

1280591 is an equidigital number, since it uses as much as digits as its factorization.

1280591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98520.

The product of its (nonzero) digits is 720, while the sum is 26.

The square root of 1280591 is about 1131.6320073239. The cubic root of 1280591 is about 108.5934127260.

The spelling of 1280591 in words is "one million, two hundred eighty thousand, five hundred ninety-one".