1665173 has 2 divisors, whose sum is σ = 1665174. Its totient is φ = 1665172.

The previous prime is 1665161. The next prime is 1665197. The reversal of 1665173 is 3715661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1036324 + 628849 = 1018^2 + 793^2 .

It is a cyclic number.

It is not a de Polignac number, because 1665173 - 2⁶ = 1665109 is a prime.

It is a super-2 number, since 2×1665173² = 5545602239858, which contains 22 as substring.

It is equal to p₁₂₅₆₈₇ and since 1665173 and 125687 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1665143) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 832586 + 832587.

It is an arithmetic number, because the mean of its divisors is an integer number (832587).

2^1665173 is an apocalyptic number.

It is an amenable number.

1665173 is a deficient number, since it is larger than the sum of its proper divisors (1).

1665173 is an equidigital number, since it uses as much as digits as its factorization.

1665173 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3780, while the sum is 29.

The square root of 1665173 is about 1290.4158244535. The cubic root of 1665173 is about 118.5276808105.

The spelling of 1665173 in words is "one million, six hundred sixty-five thousand, one hundred seventy-three".