665665522 has 8 divisors (see below), whose sum is σ = 998641116. Its totient is φ = 332785152.

The previous prime is 665665493. The next prime is 665665523. The reversal of 665665522 is 225566566.

It can be written as a sum of positive squares in 2 ways, for example, as 618069321 + 47596201 = 24861^2 + 6899^2 .

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

It is a super-2 number, since 2×665665522² = 886221174359064968, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (665665523) 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, 2523 + ... + 36574.

Almost surely, 2^665665522 is an apocalyptic number.

665665522 is a deficient number, since it is larger than the sum of its proper divisors (332975594).

665665522 is a wasteful number, since it uses less digits than its factorization.

665665522 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47612.

The product of its digits is 648000, while the sum is 43.

The square root of 665665522 is about 25800.4946076621. The cubic root of 665665522 is about 873.1429554465.

The spelling of 665665522 in words is "six hundred sixty-five million, six hundred sixty-five thousand, five hundred twenty-two".