65643564825 has 18 divisors (see below), whose sum is σ = 117574918734. Its totient is φ = 35009901120.

The previous prime is 65643564773. The next prime is 65643564827. The reversal of 65643564825 is 52846534656.

65643564825 is a `hidden beast` number, since 6 + 56 + 4 + 3 + 564 + 8 + 25 = 666.

65643564825 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 237036816 + 65406528009 = 15396^2 + 255747^2 .

It is not a de Polignac number, because 65643564825 - 2¹³ = 65643556633 is a prime.

It is not an unprimeable number, because it can be changed into a prime (65643564827) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 145874364 + ... + 145874813.

Almost surely, 2^65643564825 is an apocalyptic number.

It is an amenable number.

65643564825 is a deficient number, since it is larger than the sum of its proper divisors (51931353909).

65643564825 is a wasteful number, since it uses less digits than its factorization.

65643564825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 291749193 (or 291749185 counting only the distinct ones).

The product of its digits is 20736000, while the sum is 54.

The spelling of 65643564825 in words is "sixty-five billion, six hundred forty-three million, five hundred sixty-four thousand, eight hundred twenty-five".