641985 has 16 divisors (see below), whose sum is σ = 1038336. Its totient is φ = 338688.

The previous prime is 641981. The next prime is 642011. The reversal of 641985 is 589146.

641985 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 641985 - 2² = 641981 is a prime.

It is not an unprimeable number, because it can be changed into a prime (641981) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1737 + ... + 2073.

It is an arithmetic number, because the mean of its divisors is an integer number (64896).

2⁶⁴¹⁹⁸⁵ is an apocalyptic number.

It is an amenable number.

641985 is a deficient number, since it is larger than the sum of its proper divisors (396351).

641985 is a wasteful number, since it uses less digits than its factorization.

641985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 472.

The product of its digits is 8640, while the sum is 33.

The square root of 641985 is about 801.2396645199. The cubic root of 641985 is about 86.2663904998.

The spelling of 641985 in words is "six hundred forty-one thousand, nine hundred eighty-five".