7887665 has 4 divisors (see below), whose sum is σ = 9465204. Its totient is φ = 6310128.

The previous prime is 7887661. The next prime is 7887707. The reversal of 7887665 is 5667887.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5667887 = 197 ⋅28771.

It can be written as a sum of positive squares in 2 ways, for example, as 5276209 + 2611456 = 2297^2 + 1616^2 .

It is a cyclic number.

It is not a de Polignac number, because 7887665 - 2² = 7887661 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7887661) 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, 788762 + ... + 788771.

It is an arithmetic number, because the mean of its divisors is an integer number (2366301).

Almost surely, 2^7887665 is an apocalyptic number.

It is an amenable number.

7887665 is a deficient number, since it is larger than the sum of its proper divisors (1577539).

7887665 is a wasteful number, since it uses less digits than its factorization.

7887665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1577538.

The product of its digits is 564480, while the sum is 47.

The square root of 7887665 is about 2808.4987092751. The cubic root of 7887665 is about 199.0594588452.

The spelling of 7887665 in words is "seven million, eight hundred eighty-seven thousand, six hundred sixty-five".