643724055 has 48 divisors (see below), whose sum is σ = 1204047936. Its totient is φ = 316270080.

The previous prime is 643724051. The next prime is 643724063. The reversal of 643724055 is 550427346.

643724055 is a `hidden beast` number, since 643 + 7 + 2 + 4 + 0 + 5 + 5 = 666.

It is not a de Polignac number, because 643724055 - 2² = 643724051 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643724051) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 433915 + ... + 435395.

It is an arithmetic number, because the mean of its divisors is an integer number (25084332).

Almost surely, 2^643724055 is an apocalyptic number.

643724055 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

643724055 is a deficient number, since it is larger than the sum of its proper divisors (560323881).

643724055 is a wasteful number, since it uses less digits than its factorization.

643724055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2248 (or 2245 counting only the distinct ones).

The product of its (nonzero) digits is 100800, while the sum is 36.

The square root of 643724055 is about 25371.7176202164. The cubic root of 643724055 is about 863.4421513113.

The spelling of 643724055 in words is "six hundred forty-three million, seven hundred twenty-four thousand, fifty-five".