3987765 has 32 divisors (see below), whose sum is σ = 7180800. Its totient is φ = 2099520.

The previous prime is 3987757. The next prime is 3987769. The reversal of 3987765 is 5677893.

It is a happy number.

It is not a de Polignac number, because 3987765 - 2³ = 3987757 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

3987765 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 3987765.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3987769) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 14580 + ... + 14850.

It is an arithmetic number, because the mean of its divisors is an integer number (224400).

Almost surely, 2^3987765 is an apocalyptic number.

It is an amenable number.

3987765 is a deficient number, since it is larger than the sum of its proper divisors (3193035).

3987765 is a wasteful number, since it uses less digits than its factorization.

3987765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 394 (or 388 counting only the distinct ones).

The product of its digits is 317520, while the sum is 45.

The square root of 3987765 is about 1996.9389074281. The cubic root of 3987765 is about 158.5780911319.

The spelling of 3987765 in words is "three million, nine hundred eighty-seven thousand, seven hundred sixty-five".