643496105 has 16 divisors (see below), whose sum is σ = 891081984. Its totient is φ = 436968000.

The previous prime is 643496081. The next prime is 643496111. The reversal of 643496105 is 501694346.

It is not a de Polignac number, because 643496105 - 2²⁰ = 642447529 is a prime.

It is a Smith number, since the sum of its digits (38) 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 an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 85646 + ... + 92855.

It is an arithmetic number, because the mean of its divisors is an integer number (55692624).

Almost surely, 2^643496105 is an apocalyptic number.

It is an amenable number.

643496105 is a deficient number, since it is larger than the sum of its proper divisors (247585879).

643496105 is a wasteful number, since it uses less digits than its factorization.

643496105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 178616.

The product of its (nonzero) digits is 77760, while the sum is 38.

The square root of 643496105 is about 25367.2250157561. The cubic root of 643496105 is about 863.3402210542.

The spelling of 643496105 in words is "six hundred forty-three million, four hundred ninety-six thousand, one hundred five".