2605640563 has 4 divisors (see below), whose sum is σ = 2742779560. Its totient is φ = 2468501568.

The previous prime is 2605640561. The next prime is 2605640579. The reversal of 2605640563 is 3650465062.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3650465062 = 2 ⋅1825232531.

It is a cyclic number.

It is not a de Polignac number, because 2605640563 - 2¹ = 2605640561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2605640561) 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, 68569470 + ... + 68569507.

It is an arithmetic number, because the mean of its divisors is an integer number (685694890).

Almost surely, 2^2605640563 is an apocalyptic number.

2605640563 is a deficient number, since it is larger than the sum of its proper divisors (137138997).

2605640563 is a wasteful number, since it uses less digits than its factorization.

2605640563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137138996.

The product of its (nonzero) digits is 129600, while the sum is 37.

The square root of 2605640563 is about 51045.4754410222. The cubic root of 2605640563 is about 1376.0625286719.

The spelling of 2605640563 in words is "two billion, six hundred five million, six hundred forty thousand, five hundred sixty-three".