1665340825 has 36 divisors (see below), whose sum is σ = 2235543300. Its totient is φ = 1229962240.

The previous prime is 1665340813. The next prime is 1665340847. The reversal of 1665340825 is 5280435661.

It can be written as a sum of positive squares in 18 ways, for example, as 915183504 + 750157321 = 30252^2 + 27389^2 .

It is not a de Polignac number, because 1665340825 - 2⁷ = 1665340697 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 380751 + ... + 385099.

It is an arithmetic number, because the mean of its divisors is an integer number (62098425).

Almost surely, 2^1665340825 is an apocalyptic number.

It is an amenable number.

1665340825 is a deficient number, since it is larger than the sum of its proper divisors (570202475).

1665340825 is a wasteful number, since it uses less digits than its factorization.

1665340825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4446 (or 4424 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 40.

The square root of 1665340825 is about 40808.5876378980. The cubic root of 1665340825 is about 1185.3166262699.

The spelling of 1665340825 in words is "one billion, six hundred sixty-five million, three hundred forty thousand, eight hundred twenty-five".