641869 has 6 divisors (see below), whose sum is σ = 682154. Its totient is φ = 603840.

The previous prime is 641867. The next prime is 641873. The reversal of 641869 is 968146.

It can be written as a sum of positive squares in 3 ways, for example, as 316969 + 324900 = 563^2 + 570^2 .

It is not a de Polignac number, because 641869 - 2¹ = 641867 is a prime.

It is a super-2 number, since 2×641869² = 823991626322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 822 + ... + 1399.

2⁶⁴¹⁸⁶⁹ is an apocalyptic number.

It is an amenable number.

641869 is a deficient number, since it is larger than the sum of its proper divisors (40285).

641869 is a wasteful number, since it uses less digits than its factorization.

641869 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2255 (or 2238 counting only the distinct ones).

The product of its digits is 10368, while the sum is 34.

The square root of 641869 is about 801.1672734205. The cubic root of 641869 is about 86.2611943742.

The spelling of 641869 in words is "six hundred forty-one thousand, eight hundred sixty-nine".