641679 has 8 divisors (see below), whose sum is σ = 864000. Its totient is φ = 423576.

The previous prime is 641639. The next prime is 641681. The reversal of 641679 is 976146.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 641679 - 2⁷ = 641551 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641639) 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 7 ways as a sum of consecutive naturals, for example, 679 + ... + 1320.

It is an arithmetic number, because the mean of its divisors is an integer number (108000).

2⁶⁴¹⁶⁷⁹ is an apocalyptic number.

641679 is a deficient number, since it is larger than the sum of its proper divisors (222321).

641679 is a wasteful number, since it uses less digits than its factorization.

641679 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2109.

The product of its digits is 9072, while the sum is 33.

The square root of 641679 is about 801.0486876589. The cubic root of 641679 is about 86.2526821262.

The spelling of 641679 in words is "six hundred forty-one thousand, six hundred seventy-nine".