641866705 has 32 divisors (see below), whose sum is σ = 839946240. Its totient is φ = 469048320.

The previous prime is 641866691. The next prime is 641866717. The reversal of 641866705 is 507668146.

It is a happy number.

It is not a de Polignac number, because 641866705 - 2¹⁹ = 641342417 is a prime.

It is a super-3 number, since 3×641866705³ (a number of 27 digits) contains 333 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 408832 + ... + 410398.

It is an arithmetic number, because the mean of its divisors is an integer number (26248320).

Almost surely, 2^641866705 is an apocalyptic number.

It is an amenable number.

641866705 is a deficient number, since it is larger than the sum of its proper divisors (198079535).

641866705 is a wasteful number, since it uses less digits than its factorization.

641866705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1729.

The product of its (nonzero) digits is 241920, while the sum is 43.

The square root of 641866705 is about 25335.0884150816. The cubic root of 641866705 is about 862.6109156526.

The spelling of 641866705 in words is "six hundred forty-one million, eight hundred sixty-six thousand, seven hundred five".