2540646565 has 8 divisors (see below), whose sum is σ = 3050753400. Its totient is φ = 2031198912.

The previous prime is 2540646527. The next prime is 2540646593. The reversal of 2540646565 is 5656460452.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 6832996 + 2533813569 = 2614^2 + 50337^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 2540646565 - 2²³ = 2532257957 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 156274 + ... + 171763.

It is an arithmetic number, because the mean of its divisors is an integer number (381344175).

Almost surely, 2^2540646565 is an apocalyptic number.

It is an amenable number.

2540646565 is a deficient number, since it is larger than the sum of its proper divisors (510106835).

2540646565 is a wasteful number, since it uses less digits than its factorization.

2540646565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 329591.

The product of its (nonzero) digits is 864000, while the sum is 43.

The square root of 2540646565 is about 50404.8268025990. The cubic root of 2540646565 is about 1364.5247514759.

The spelling of 2540646565 in words is "two billion, five hundred forty million, six hundred forty-six thousand, five hundred sixty-five".