645606555545 has 16 divisors (see below), whose sum is σ = 902109000960. Its totient is φ = 434348775744.

The previous prime is 645606555541. The next prime is 645606555557. The reversal of 645606555545 is 545555606546.

645606555545 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 645606555545 - 2² = 645606555541 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (645606555541) 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, 174016085 + ... + 174019794.

It is an arithmetic number, because the mean of its divisors is an integer number (56381812560).

Almost surely, 2^645606555545 is an apocalyptic number.

It is an amenable number.

645606555545 is a deficient number, since it is larger than the sum of its proper divisors (256502445415).

645606555545 is a wasteful number, since it uses less digits than its factorization.

645606555545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 348035944.

The product of its (nonzero) digits is 54000000, while the sum is 56.

The spelling of 645606555545 in words is "six hundred forty-five billion, six hundred six million, five hundred fifty-five thousand, five hundred forty-five".