641144021 has 32 divisors (see below), whose sum is σ = 784816128. Its totient is φ = 511917120.

The previous prime is 641144011. The next prime is 641144027. The reversal of 641144021 is 120441146.

It is a happy number.

641144021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 641144021 - 2⁶ = 641143957 is a prime.

It is a super-2 number, since 2×641144021² = 822131311328096882, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641144027) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1936826 + ... + 1937156.

It is an arithmetic number, because the mean of its divisors is an integer number (24525504).

Almost surely, 2^641144021 is an apocalyptic number.

It is an amenable number.

641144021 is a deficient number, since it is larger than the sum of its proper divisors (143672107).

641144021 is a wasteful number, since it uses less digits than its factorization.

641144021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 641.

The product of its (nonzero) digits is 768, while the sum is 23.

The square root of 641144021 is about 25320.8218863448. The cubic root of 641144021 is about 862.2870533871.

Adding to 641144021 its reverse (120441146), we get a palindrome (761585167).

The spelling of 641144021 in words is "six hundred forty-one million, one hundred forty-four thousand, twenty-one".