645753870512 has 20 divisors (see below), whose sum is σ = 1251267595296. Its totient is φ = 322846104000.

The previous prime is 645753870511. The next prime is 645753870569. The reversal of 645753870512 is 215078357546.

It is a super-2 number, since 2×645753870512² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (645753870511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1753688 + ... + 2089719.

Almost surely, 2^645753870512 is an apocalyptic number.

It is an amenable number.

645753870512 is a deficient number, since it is larger than the sum of its proper divisors (605513724784).

645753870512 is a wasteful number, since it uses less digits than its factorization.

645753870512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3853916 (or 3853910 counting only the distinct ones).

The product of its (nonzero) digits is 7056000, while the sum is 53.

The spelling of 645753870512 in words is "six hundred forty-five billion, seven hundred fifty-three million, eight hundred seventy thousand, five hundred twelve".