665487187 has 4 divisors (see below), whose sum is σ = 665556480. Its totient is φ = 665417896.

The previous prime is 665487181. The next prime is 665487209. The reversal of 665487187 is 781784566.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 665487187 - 2⁷ = 665487059 is a prime.

It is a super-3 number, since 3×665487187³ (a number of 27 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (665487181) 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, 17368 + ... + 40405.

It is an arithmetic number, because the mean of its divisors is an integer number (166389120).

Almost surely, 2^665487187 is an apocalyptic number.

665487187 is a deficient number, since it is larger than the sum of its proper divisors (69293).

665487187 is a wasteful number, since it uses less digits than its factorization.

665487187 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69292.

The product of its digits is 2257920, while the sum is 52.

The square root of 665487187 is about 25797.0383377627. The cubic root of 665487187 is about 873.0649754144.

The spelling of 665487187 in words is "six hundred sixty-five million, four hundred eighty-seven thousand, one hundred eighty-seven".