665534553 has 4 divisors (see below), whose sum is σ = 887379408. Its totient is φ = 443689700.

The previous prime is 665534539. The next prime is 665534669. The reversal of 665534553 is 355435566.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 665534553 - 2¹² = 665530457 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (665534533) 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, 110922423 + ... + 110922428.

It is an arithmetic number, because the mean of its divisors is an integer number (221844852).

Almost surely, 2^665534553 is an apocalyptic number.

It is an amenable number.

665534553 is a deficient number, since it is larger than the sum of its proper divisors (221844855).

665534553 is a wasteful number, since it uses less digits than its factorization.

665534553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 221844854.

The product of its digits is 810000, while the sum is 42.

The square root of 665534553 is about 25797.9563725501. The cubic root of 665534553 is about 873.0856883674.

The spelling of 665534553 in words is "six hundred sixty-five million, five hundred thirty-four thousand, five hundred fifty-three".