645120516512 has 12 divisors (see below), whose sum is σ = 1270081016946. Its totient is φ = 322560258240.

The previous prime is 645120516437. The next prime is 645120516527. The reversal of 645120516512 is 215615021546.

It can be written as a sum of positive squares in only one way, i.e., 643402911376 + 1717605136 = 802124^2 + 41444^2 .

It is a super-2 number, since 2×645120516512² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10080008039 + ... + 10080008102.

Almost surely, 2^645120516512 is an apocalyptic number.

It is an amenable number.

645120516512 is a deficient number, since it is larger than the sum of its proper divisors (624960500434).

645120516512 is a wasteful number, since it uses less digits than its factorization.

645120516512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20160016151 (or 20160016143 counting only the distinct ones).

The product of its (nonzero) digits is 72000, while the sum is 38.

The spelling of 645120516512 in words is "six hundred forty-five billion, one hundred twenty million, five hundred sixteen thousand, five hundred twelve".