643557755346 has 32 divisors (see below), whose sum is σ = 1404642816000. Its totient is φ = 194945723280.

The previous prime is 643557755317. The next prime is 643557755377.

It is a happy number.

643557755346 is nontrivially palindromic in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 643557755346.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1613646 + ... + 1972553.

It is an arithmetic number, because the mean of its divisors is an integer number (43895088000).

Almost surely, 2^643557755346 is an apocalyptic number.

643557755346 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

643557755346 is an abundant number, since it is smaller than the sum of its proper divisors (761085060654).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

643557755346 is a wasteful number, since it uses less digits than its factorization.

643557755346 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3588934.

The product of its digits is 158760000, while the sum is 60.

The spelling of 643557755346 in words is "six hundred forty-three billion, five hundred fifty-seven million, seven hundred fifty-five thousand, three hundred forty-six".