643153555 has 16 divisors (see below), whose sum is σ = 842446944. Its totient is φ = 467470080.

The previous prime is 643153529. The next prime is 643153597. The reversal of 643153555 is 555351346.

It is not a de Polignac number, because 643153555 - 2⁵ = 643153523 is a prime.

It is a Duffinian number.

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, 155089 + ... + 159181.

It is an arithmetic number, because the mean of its divisors is an integer number (52652934).

Almost surely, 2^643153555 is an apocalyptic number.

643153555 is a deficient number, since it is larger than the sum of its proper divisors (199293389).

643153555 is a wasteful number, since it uses less digits than its factorization.

643153555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6966.

The product of its digits is 135000, while the sum is 37.

The square root of 643153555 is about 25360.4722944980. The cubic root of 643153555 is about 863.1870009170.

The spelling of 643153555 in words is "six hundred forty-three million, one hundred fifty-three thousand, five hundred fifty-five".