643741 has 8 divisors (see below), whose sum is σ = 753984. Its totient is φ = 538080.

The previous prime is 643729. The next prime is 643751. The reversal of 643741 is 147346.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-643741 is a prime.

It is a super-3 number, since 3×643741³ = 800303591133354063, which contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643751) 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, 835 + ... + 1408.

It is an arithmetic number, because the mean of its divisors is an integer number (94248).

2⁶⁴³⁷⁴¹ is an apocalyptic number.

It is an amenable number.

643741 is a deficient number, since it is larger than the sum of its proper divisors (110243).

643741 is a wasteful number, since it uses less digits than its factorization.

643741 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2291.

The product of its digits is 2016, while the sum is 25.

The square root of 643741 is about 802.3347181819. The cubic root of 643741 is about 86.3449727487.

The spelling of 643741 in words is "six hundred forty-three thousand, seven hundred forty-one".