643244504545 has 8 divisors (see below), whose sum is σ = 786457432296. Its totient is φ = 504886252416.

The previous prime is 643244504519. The next prime is 643244504569. The reversal of 643244504545 is 545405442346.

It can be written as a sum of positive squares in 4 ways, for example, as 100430680464 + 542813824081 = 316908^2 + 736759^2 .

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 643244504545 - 2⁷ = 643244504417 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 643244504495 and 643244504504.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1213668612 + ... + 1213669141.

It is an arithmetic number, because the mean of its divisors is an integer number (98307179037).

Almost surely, 2^643244504545 is an apocalyptic number.

It is an amenable number.

643244504545 is a deficient number, since it is larger than the sum of its proper divisors (143212927751).

643244504545 is a wasteful number, since it uses less digits than its factorization.

643244504545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2427337811.

The product of its (nonzero) digits is 4608000, while the sum is 46.

The spelling of 643244504545 in words is "six hundred forty-three billion, two hundred forty-four million, five hundred four thousand, five hundred forty-five".