665511567 has 16 divisors (see below), whose sum is σ = 1021413120. Its totient is φ = 377554752.

The previous prime is 665511557. The next prime is 665511569. The reversal of 665511567 is 765115566.

It is not a de Polignac number, because 665511567 - 2²² = 661317263 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665511569) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 111078 + ... + 116915.

It is an arithmetic number, because the mean of its divisors is an integer number (63838320).

Almost surely, 2^665511567 is an apocalyptic number.

665511567 is a deficient number, since it is larger than the sum of its proper divisors (355901553).

665511567 is a wasteful number, since it uses less digits than its factorization.

665511567 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 228142.

The product of its digits is 189000, while the sum is 42.

The square root of 665511567 is about 25797.5108682989. The cubic root of 665511567 is about 873.0756368088.

The spelling of 665511567 in words is "six hundred sixty-five million, five hundred eleven thousand, five hundred sixty-seven".