1665625 has 24 divisors (see below), whose sum is σ = 2296728. Its totient is φ = 1200000.

The previous prime is 1665623. The next prime is 1665647. The reversal of 1665625 is 5265661.

1665625 is nontrivially palindromic in base 4.

It can be written as a sum of positive squares in 12 ways, for example, as 1364224 + 301401 = 1168^2 + 549^2 .

It is not a de Polignac number, because 1665625 - 2¹ = 1665623 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1665623) 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 23 ways as a sum of consecutive naturals, for example, 40605 + ... + 40645.

It is an arithmetic number, because the mean of its divisors is an integer number (95697).

2^1665625 is an apocalyptic number.

It is an amenable number.

1665625 is a deficient number, since it is larger than the sum of its proper divisors (631103).

1665625 is an frugal number, since it uses more digits than its factorization.

1665625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79 (or 59 counting only the distinct ones).

The product of its digits is 10800, while the sum is 31.

The square root of 1665625 is about 1290.5909499140. The cubic root of 1665625 is about 118.5384043540.

The spelling of 1665625 in words is "one million, six hundred sixty-five thousand, six hundred twenty-five".