645758520747 has 16 divisors (see below), whose sum is σ = 862490549760. Its totient is φ = 429766679232.

The previous prime is 645758520721. The next prime is 645758520751. The reversal of 645758520747 is 747025857546.

645758520747 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 645758520747 - 2³⁶ = 577039044011 is a prime.

It is not an unprimeable number, because it can be changed into a prime (645758520787) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4357623 + ... + 4503375.

It is an arithmetic number, because the mean of its divisors is an integer number (53905659360).

Almost surely, 2^645758520747 is an apocalyptic number.

645758520747 is a deficient number, since it is larger than the sum of its proper divisors (216732029013).

645758520747 is a wasteful number, since it uses less digits than its factorization.

645758520747 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148282.

The product of its (nonzero) digits is 65856000, while the sum is 60.

The spelling of 645758520747 in words is "six hundred forty-five billion, seven hundred fifty-eight million, five hundred twenty thousand, seven hundred forty-seven".