643690585907 has 16 divisors (see below), whose sum is σ = 677316089472. Its totient is φ = 611178462720.

The previous prime is 643690585903. The next prime is 643690585927. The reversal of 643690585907 is 709585096346.

It is a cyclic number.

It is not a de Polignac number, because 643690585907 - 2² = 643690585903 is a prime.

It is a super-3 number, since 3×643690585907³ (a number of 36 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (62) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 643690585907.

It is not an unprimeable number, because it can be changed into a prime (643690585903) 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, 1328498 + ... + 1747079.

It is an arithmetic number, because the mean of its divisors is an integer number (42332255592).

Almost surely, 2^643690585907 is an apocalyptic number.

643690585907 is a deficient number, since it is larger than the sum of its proper divisors (33625503565).

643690585907 is a wasteful number, since it uses less digits than its factorization.

643690585907 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3075758.

The product of its (nonzero) digits is 48988800, while the sum is 62.

The spelling of 643690585907 in words is "six hundred forty-three billion, six hundred ninety million, five hundred eighty-five thousand, nine hundred seven".