645589985546 has 48 divisors (see below), whose sum is σ = 1082260980864. Its totient is φ = 288535764000.

The previous prime is 645589985539. The next prime is 645589985597.

645589985546 is nontrivially palindromic in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 53476691 + ... + 53488761.

It is an arithmetic number, because the mean of its divisors is an integer number (22547103768).

Almost surely, 2^645589985546 is an apocalyptic number.

645589985546 is a deficient number, since it is larger than the sum of its proper divisors (436670995318).

645589985546 is a wasteful number, since it uses less digits than its factorization.

645589985546 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15779 (or 15768 counting only the distinct ones).

The product of its digits is 1866240000, while the sum is 74.

The spelling of 645589985546 in words is "six hundred forty-five billion, five hundred eighty-nine million, nine hundred eighty-five thousand, five hundred forty-six".