643065361 has 16 divisors (see below), whose sum is σ = 667408896. Its totient is φ = 619200000.

The previous prime is 643065347. The next prime is 643065373. The reversal of 643065361 is 163560346.

It is a cyclic number.

It is not a de Polignac number, because 643065361 - 2⁵ = 643065329 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (643065331) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1491816 + ... + 1492246.

It is an arithmetic number, because the mean of its divisors is an integer number (41713056).

Almost surely, 2^643065361 is an apocalyptic number.

It is an amenable number.

643065361 is a deficient number, since it is larger than the sum of its proper divisors (24343535).

643065361 is a wasteful number, since it uses less digits than its factorization.

643065361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 864.

The product of its (nonzero) digits is 38880, while the sum is 34.

The square root of 643065361 is about 25358.7334265732. The cubic root of 643065361 is about 863.1475435724.

The spelling of 643065361 in words is "six hundred forty-three million, sixty-five thousand, three hundred sixty-one".