1298665 has 4 divisors (see below), whose sum is σ = 1558404. Its totient is φ = 1038928.

The previous prime is 1298653. The next prime is 1298699. The reversal of 1298665 is 5668921.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5668921 = 1493 ⋅3797.

It can be written as a sum of positive squares in 2 ways, for example, as 853776 + 444889 = 924^2 + 667^2 .

It is a cyclic number.

It is not a de Polignac number, because 1298665 - 2⁷ = 1298537 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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, 129862 + ... + 129871.

It is an arithmetic number, because the mean of its divisors is an integer number (389601).

2^1298665 is an apocalyptic number.

It is an amenable number.

1298665 is a deficient number, since it is larger than the sum of its proper divisors (259739).

1298665 is an equidigital number, since it uses as much as digits as its factorization.

1298665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 259738.

The product of its digits is 25920, while the sum is 37.

The square root of 1298665 is about 1139.5898384945. The cubic root of 1298665 is about 109.1019162925.

The spelling of 1298665 in words is "one million, two hundred ninety-eight thousand, six hundred sixty-five".