1665245 has 4 divisors (see below), whose sum is σ = 1998300. Its totient is φ = 1332192.

The previous prime is 1665233. The next prime is 1665247. The reversal of 1665245 is 5425661.

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 470596 + 1194649 = 686^2 + 1093^2 .

It is a cyclic number.

It is not a de Polignac number, because 1665245 - 2¹⁶ = 1599709 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1665247) 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, 166520 + ... + 166529.

It is an arithmetic number, because the mean of its divisors is an integer number (499575).

2^1665245 is an apocalyptic number.

It is an amenable number.

1665245 is a deficient number, since it is larger than the sum of its proper divisors (333055).

1665245 is an equidigital number, since it uses as much as digits as its factorization.

1665245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333054.

The product of its digits is 7200, while the sum is 29.

The square root of 1665245 is about 1290.4437221359. The cubic root of 1665245 is about 118.5293891155.

The spelling of 1665245 in words is "one million, six hundred sixty-five thousand, two hundred forty-five".