643215853169 has 8 divisors (see below), whose sum is σ = 693902120040. Its totient is φ = 593957368576.

The previous prime is 643215853141. The next prime is 643215853201. The reversal of 643215853169 is 961358512346.

It can be written as a sum of positive squares in 4 ways, for example, as 424467886144 + 218747967025 = 651512^2 + 467705^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 643215853169 - 2²⁰ = 643214804593 is a prime.

It is a super-2 number, since 2×643215853169² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (53).

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 643215853169.

It is not an unprimeable number, because it can be changed into a prime (643215853369) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 356944634 + ... + 356946435.

It is an arithmetic number, because the mean of its divisors is an integer number (86737765005).

Almost surely, 2^643215853169 is an apocalyptic number.

It is an amenable number.

643215853169 is a deficient number, since it is larger than the sum of its proper divisors (50686266871).

643215853169 is a wasteful number, since it uses less digits than its factorization.

643215853169 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 713891139.

The product of its digits is 4665600, while the sum is 53.

The spelling of 643215853169 in words is "six hundred forty-three billion, two hundred fifteen million, eight hundred fifty-three thousand, one hundred sixty-nine".