643139 has 8 divisors (see below), whose sum is σ = 744960. Its totient is φ = 543816.

The previous prime is 643129. The next prime is 643183. The reversal of 643139 is 931346.

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

It is not a de Polignac number, because 643139 - 2¹² = 639043 is a prime.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 643139.

It is not an unprimeable number, because it can be changed into a prime (643129) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29 + ... + 1134.

It is an arithmetic number, because the mean of its divisors is an integer number (93120).

2⁶⁴³¹³⁹ is an apocalyptic number.

643139 is a deficient number, since it is larger than the sum of its proper divisors (101821).

643139 is a wasteful number, since it uses less digits than its factorization.

643139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1249.

The product of its digits is 1944, while the sum is 26.

The square root of 643139 is about 801.9594752854. The cubic root of 643139 is about 86.3180489366.

The spelling of 643139 in words is "six hundred forty-three thousand, one hundred thirty-nine".