641533 has 4 divisors (see below), whose sum is σ = 643680. Its totient is φ = 639388.

The previous prime is 641521. The next prime is 641549. The reversal of 641533 is 335146.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-641533 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 (641513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 535 + ... + 1252.

It is an arithmetic number, because the mean of its divisors is an integer number (160920).

2⁶⁴¹⁵³³ is an apocalyptic number.

It is an amenable number.

641533 is a deficient number, since it is larger than the sum of its proper divisors (2147).

641533 is a wasteful number, since it uses less digits than its factorization.

641533 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2146.

The product of its digits is 1080, while the sum is 22.

The square root of 641533 is about 800.9575519339. The cubic root of 641533 is about 86.2461399939.

Adding to 641533 its reverse (335146), we get a palindrome (976679).

The spelling of 641533 in words is "six hundred forty-one thousand, five hundred thirty-three".