1242665 has 4 divisors (see below), whose sum is σ = 1491204. Its totient is φ = 994128.

The previous prime is 1242643. The next prime is 1242739. The reversal of 1242665 is 5662421.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 946729 + 295936 = 973^2 + 544^2 .

It is a cyclic number.

It is not a de Polignac number, because 1242665 - 2⁶ = 1242601 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, 124262 + ... + 124271.

It is an arithmetic number, because the mean of its divisors is an integer number (372801).

2^1242665 is an apocalyptic number.

It is an amenable number.

1242665 is a deficient number, since it is larger than the sum of its proper divisors (248539).

1242665 is an equidigital number, since it uses as much as digits as its factorization.

1242665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 248538.

The product of its digits is 2880, while the sum is 26.

The square root of 1242665 is about 1114.7488506386. The cubic root of 1242665 is about 107.5106173036.

The spelling of 1242665 in words is "one million, two hundred forty-two thousand, six hundred sixty-five".