645817689583 has 8 divisors (see below), whose sum is σ = 704736193536. Its totient is φ = 586933819800.

The previous prime is 645817689571. The next prime is 645817689611. The reversal of 645817689583 is 385986718546.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 645817689583 - 2¹⁷ = 645817558511 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 (645817689533) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8619541 + ... + 8694142.

It is an arithmetic number, because the mean of its divisors is an integer number (88092024192).

Almost surely, 2^645817689583 is an apocalyptic number.

645817689583 is a deficient number, since it is larger than the sum of its proper divisors (58918503953).

645817689583 is a wasteful number, since it uses less digits than its factorization.

645817689583 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17317085.

The product of its digits is 348364800, while the sum is 70.

The spelling of 645817689583 in words is "six hundred forty-five billion, eight hundred seventeen million, six hundred eighty-nine thousand, five hundred eighty-three".