641216717 has 4 divisors (see below), whose sum is σ = 644017020. Its totient is φ = 638416416.

The previous prime is 641216713. The next prime is 641216783. The reversal of 641216717 is 717612146.

It is a happy number.

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 622302916 + 18913801 = 24946^2 + 4349^2 .

It is a cyclic number.

It is not a de Polignac number, because 641216717 - 2² = 641216713 is a prime.

It is a super-2 number, since 2×641216717² = 822317756320516178, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641216711) 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, 1399808 + ... + 1400265.

It is an arithmetic number, because the mean of its divisors is an integer number (161004255).

Almost surely, 2^641216717 is an apocalyptic number.

It is an amenable number.

641216717 is a deficient number, since it is larger than the sum of its proper divisors (2800303).

641216717 is a wasteful number, since it uses less digits than its factorization.

641216717 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2800302.

The product of its digits is 14112, while the sum is 35.

The square root of 641216717 is about 25322.2573440837. The cubic root of 641216717 is about 862.3196422431.

The spelling of 641216717 in words is "six hundred forty-one million, two hundred sixteen thousand, seven hundred seventeen".