663041605 has 4 divisors (see below), whose sum is σ = 795649932. Its totient is φ = 530433280.

The previous prime is 663041579. The next prime is 663041623. The reversal of 663041605 is 506140366.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 506140366 = 2 ⋅253070183.

It can be written as a sum of positive squares in 2 ways, for example, as 373803556 + 289238049 = 19334^2 + 17007^2 .

It is not a de Polignac number, because 663041605 - 2⁵ = 663041573 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66304156 + ... + 66304165.

It is an arithmetic number, because the mean of its divisors is an integer number (198912483).

Almost surely, 2^663041605 is an apocalyptic number.

It is an amenable number.

663041605 is a deficient number, since it is larger than the sum of its proper divisors (132608327).

663041605 is a wasteful number, since it uses less digits than its factorization.

663041605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132608326.

The product of its (nonzero) digits is 12960, while the sum is 31.

The square root of 663041605 is about 25749.5942686482. The cubic root of 663041605 is about 871.9941945613.

The spelling of 663041605 in words is "six hundred sixty-three million, forty-one thousand, six hundred five".