65606561 has 4 divisors (see below), whose sum is σ = 65644224. Its totient is φ = 65568900.

The previous prime is 65606551. The next prime is 65606579. The reversal of 65606561 is 16560656.

65606561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 65606561 - 2²² = 61412257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65606551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16085 + ... + 19746.

It is an arithmetic number, because the mean of its divisors is an integer number (16411056).

Almost surely, 2^65606561 is an apocalyptic number.

It is an amenable number.

65606561 is a deficient number, since it is larger than the sum of its proper divisors (37663).

65606561 is a wasteful number, since it uses less digits than its factorization.

65606561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37662.

The product of its (nonzero) digits is 32400, while the sum is 35.

The square root of 65606561 is about 8099.7877132676. The cubic root of 65606561 is about 403.3193801759.

The spelling of 65606561 in words is "sixty-five million, six hundred six thousand, five hundred sixty-one".