665116511 has 8 divisors (see below), whose sum is σ = 667484064. Its totient is φ = 662754400.

The previous prime is 665116471. The next prime is 665116547. The reversal of 665116511 is 115611566.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 665116511 - 2¹⁰ = 665115487 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665113511) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 520205 + ... + 521481.

It is an arithmetic number, because the mean of its divisors is an integer number (83435508).

Almost surely, 2^665116511 is an apocalyptic number.

665116511 is a deficient number, since it is larger than the sum of its proper divisors (2367553).

665116511 is a wasteful number, since it uses less digits than its factorization.

665116511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2721.

The product of its digits is 5400, while the sum is 32.

The square root of 665116511 is about 25789.8528689095. The cubic root of 665116511 is about 872.9028464038.

The spelling of 665116511 in words is "six hundred sixty-five million, one hundred sixteen thousand, five hundred eleven".