645549122345 has 32 divisors (see below), whose sum is σ = 841743687456. Its totient is φ = 473352601600.

The previous prime is 645549122291. The next prime is 645549122371. The reversal of 645549122345 is 543221945546.

It can be written as a sum of positive squares in 16 ways, for example, as 161595156121 + 483953966224 = 401989^2 + 695668^2 .

It is not a de Polignac number, because 645549122345 - 2²⁸ = 645280686889 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 645549122293 and 645549122302.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1774865 + ... + 2107425.

It is an arithmetic number, because the mean of its divisors is an integer number (26304490233).

Almost surely, 2^645549122345 is an apocalyptic number.

It is an amenable number.

645549122345 is a deficient number, since it is larger than the sum of its proper divisors (196194565111).

645549122345 is a wasteful number, since it uses less digits than its factorization.

645549122345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333181.

The product of its digits is 5184000, while the sum is 50.

The spelling of 645549122345 in words is "six hundred forty-five billion, five hundred forty-nine million, one hundred twenty-two thousand, three hundred forty-five".