640241555 has 8 divisors (see below), whose sum is σ = 794782800. Its totient is φ = 494531296.

The previous prime is 640241549. The next prime is 640241557. The reversal of 640241555 is 555142046.

640241555 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 640241555 - 2¹⁸ = 639979411 is a prime.

It is not an unprimeable number, because it can be changed into a prime (640241557) 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, 2207585 + ... + 2207874.

It is an arithmetic number, because the mean of its divisors is an integer number (99347850).

Almost surely, 2^640241555 is an apocalyptic number.

640241555 is a deficient number, since it is larger than the sum of its proper divisors (154541245).

640241555 is a wasteful number, since it uses less digits than its factorization.

640241555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4415493.

The product of its (nonzero) digits is 24000, while the sum is 32.

The square root of 640241555 is about 25302.9949808318. The cubic root of 640241555 is about 861.8822820569.

The spelling of 640241555 in words is "six hundred forty million, two hundred forty-one thousand, five hundred fifty-five".