7865665000 has 40 divisors (see below), whose sum is σ = 18429264810. Its totient is φ = 3146264000.

The previous prime is 7865664953. The next prime is 7865665007. The reversal of 7865665000 is 5665687.

It can be written as a sum of positive squares in 5 ways, for example, as 26687556 + 7838977444 = 5166^2 + 88538^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (7865665007) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 781567 + ... + 791566.

Almost surely, 2^7865665000 is an apocalyptic number.

It is an amenable number.

7865665000 is an abundant number, since it is smaller than the sum of its proper divisors (10563599810).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

7865665000 is a wasteful number, since it uses less digits than its factorization.

7865665000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1573159 (or 1573140 counting only the distinct ones).

The product of its (nonzero) digits is 302400, while the sum is 43.

The square root of 7865665000 is about 88688.5843837864. The cubic root of 7865665000 is about 1988.7421661556.

The spelling of 7865665000 in words is "seven billion, eight hundred sixty-five million, six hundred sixty-five thousand".