641889 has 12 divisors (see below), whose sum is σ = 940836. Its totient is φ = 421632.

The previous prime is 641881. The next prime is 641891. The reversal of 641889 is 988146.

It is a happy number.

641889 is a `hidden beast` number, since 641 + 8 + 8 + 9 = 666.

641889 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 501264 + 140625 = 708^2 + 375^2 .

It is not a de Polignac number, because 641889 - 2³ = 641881 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (641881) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 169 + ... + 1145.

It is an arithmetic number, because the mean of its divisors is an integer number (78403).

2⁶⁴¹⁸⁸⁹ is an apocalyptic number.

It is an amenable number.

641889 is a deficient number, since it is larger than the sum of its proper divisors (298947).

641889 is a wasteful number, since it uses less digits than its factorization.

641889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1056 (or 1053 counting only the distinct ones).

The product of its digits is 13824, while the sum is 36.

The square root of 641889 is about 801.1797551112. The cubic root of 641889 is about 86.2620903026.

It can be divided in two parts, 64 and 1889, that added together give a triangular number (1953 = T₆₂).

The spelling of 641889 in words is "six hundred forty-one thousand, eight hundred eighty-nine".