664432103221 has 48 divisors (see below), whose sum is σ = 701509319280. Its totient is φ = 629024901120.

The previous prime is 664432103213. The next prime is 664432103299. The reversal of 664432103221 is 122301234466.

It can be written as a sum of positive squares in 8 ways, for example, as 27675982321 + 636756120900 = 166361^2 + 797970^2 .

It is not a de Polignac number, because 664432103221 - 2³ = 664432103213 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 (664432103021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3372751695 + ... + 3372751891.

It is an arithmetic number, because the mean of its divisors is an integer number (14614777485).

Almost surely, 2^664432103221 is an apocalyptic number.

664432103221 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

It is an amenable number.

664432103221 is a deficient number, since it is larger than the sum of its proper divisors (37077216059).

664432103221 is a wasteful number, since it uses less digits than its factorization.

664432103221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 614 (or 547 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 34.

Adding to 664432103221 its reverse (122301234466), we get a palindrome (786733337687).

The spelling of 664432103221 in words is "six hundred sixty-four billion, four hundred thirty-two million, one hundred three thousand, two hundred twenty-one".