641821933 has 4 divisors (see below), whose sum is σ = 641911068. Its totient is φ = 641732800.

The previous prime is 641821907. The next prime is 641821949. The reversal of 641821933 is 339128146.

641821933 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 410386564 + 231435369 = 20258^2 + 15213^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-641821933 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 641821892 and 641821901.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641821963) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32716 + ... + 48517.

It is an arithmetic number, because the mean of its divisors is an integer number (160477767).

Almost surely, 2^641821933 is an apocalyptic number.

It is an amenable number.

641821933 is a deficient number, since it is larger than the sum of its proper divisors (89135).

641821933 is an equidigital number, since it uses as much as digits as its factorization.

641821933 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89134.

The product of its digits is 31104, while the sum is 37.

The square root of 641821933 is about 25334.2048029931. The cubic root of 641821933 is about 862.5908586773.

The spelling of 641821933 in words is "six hundred forty-one million, eight hundred twenty-one thousand, nine hundred thirty-three".