646565011 has 4 divisors (see below), whose sum is σ = 657523800. Its totient is φ = 635606224.

The previous prime is 646565009. The next prime is 646565021. The reversal of 646565011 is 110565646.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 646565011 - 2¹ = 646565009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (646565021) 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, 5479306 + ... + 5479423.

It is an arithmetic number, because the mean of its divisors is an integer number (164380950).

Almost surely, 2^646565011 is an apocalyptic number.

646565011 is a deficient number, since it is larger than the sum of its proper divisors (10958789).

646565011 is a wasteful number, since it uses less digits than its factorization.

646565011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10958788.

The product of its (nonzero) digits is 21600, while the sum is 34.

The square root of 646565011 is about 25427.6426551893. The cubic root of 646565011 is about 864.7105008689.

The spelling of 646565011 in words is "six hundred forty-six million, five hundred sixty-five thousand, eleven".