643416316205 has 16 divisors (see below), whose sum is σ = 832379331504. Its totient is φ = 474631073280.

The previous prime is 643416316201. The next prime is 643416316211. The reversal of 643416316205 is 502613614346.

It can be written as a sum of positive squares in 8 ways, for example, as 175928235844 + 467488080361 = 419438^2 + 683731^2 .

It is not a de Polignac number, because 643416316205 - 2² = 643416316201 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643416316201) 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, 5221226 + ... + 5343035.

It is an arithmetic number, because the mean of its divisors is an integer number (52023708219).

Almost surely, 2^643416316205 is an apocalyptic number.

643416316205 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

643416316205 is a deficient number, since it is larger than the sum of its proper divisors (188963015299).

643416316205 is a wasteful number, since it uses less digits than its factorization.

643416316205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10565216.

The product of its (nonzero) digits is 311040, while the sum is 41.

The spelling of 643416316205 in words is "six hundred forty-three billion, four hundred sixteen million, three hundred sixteen thousand, two hundred five".