643131 has 12 divisors (see below), whose sum is σ = 978120. Its totient is φ = 406080.

The previous prime is 643129. The next prime is 643183. The reversal of 643131 is 131346.

643131 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 643131 - 2¹ = 643129 is a prime.

It is a super-2 number, since 2×643131² = 827234966322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (643121) 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, 1710 + ... + 2051.

It is an arithmetic number, because the mean of its divisors is an integer number (81510).

2⁶⁴³¹³¹ is an apocalyptic number.

643131 is a deficient number, since it is larger than the sum of its proper divisors (334989).

643131 is a wasteful number, since it uses less digits than its factorization.

643131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3786 (or 3783 counting only the distinct ones).

The product of its digits is 216, while the sum is 18.

The square root of 643131 is about 801.9544874867. The cubic root of 643131 is about 86.3176910320.

Adding to 643131 its reverse (131346), we get a palindrome (774477).

The spelling of 643131 in words is "six hundred forty-three thousand, one hundred thirty-one".