643743 has 6 divisors (see below), whose sum is σ = 929864. Its totient is φ = 429156.

The previous prime is 643729. The next prime is 643751. The reversal of 643743 is 347346.

It is not a de Polignac number, because 643743 - 2⁹ = 643231 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643703) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 35755 + ... + 35772.

2⁶⁴³⁷⁴³ is an apocalyptic number.

643743 is a deficient number, since it is larger than the sum of its proper divisors (286121).

643743 is a wasteful number, since it uses less digits than its factorization.

643743 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71533 (or 71530 counting only the distinct ones).

The product of its digits is 6048, while the sum is 27.

The square root of 643743 is about 802.3359645435. The cubic root of 643743 is about 86.3450621686.

The spelling of 643743 in words is "six hundred forty-three thousand, seven hundred forty-three".