645509434212863 has 24 divisors (see below), whose sum is σ = 710805402042960. Its totient is φ = 585769441276800.

The previous prime is 645509434212829. The next prime is 645509434212967. The reversal of 645509434212863 is 368212434905546.

It is not a de Polignac number, because 645509434212863 - 2¹⁰ = 645509434211839 is a prime.

It is a Smith number, since the sum of its digits (62) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 645509434212796 and 645509434212805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645509434212803) 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 23 ways as a sum of consecutive naturals, for example, 1646465528 + ... + 1646857538.

It is an arithmetic number, because the mean of its divisors is an integer number (29616891751790).

Almost surely, 2^{645509434212863} is an apocalyptic number.

645509434212863 is a deficient number, since it is larger than the sum of its proper divisors (65295967830097).

645509434212863 is a wasteful number, since it uses less digits than its factorization.

645509434212863 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 416519 (or 416508 counting only the distinct ones).

The product of its (nonzero) digits is 149299200, while the sum is 62.

The spelling of 645509434212863 in words is "six hundred forty-five trillion, five hundred nine billion, four hundred thirty-four million, two hundred twelve thousand, eight hundred sixty-three".