645506006361 has 16 divisors (see below), whose sum is σ = 861293684160. Its totient is φ = 430027942400.

The previous prime is 645506006357. The next prime is 645506006399. The reversal of 645506006361 is 163600605546.

It is a cyclic number.

It is not a de Polignac number, because 645506006361 - 2² = 645506006357 is a prime.

It is not an unprimeable number, because it can be changed into a prime (645506006311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31944061 + ... + 31964261.

It is an arithmetic number, because the mean of its divisors is an integer number (53830855260).

Almost surely, 2^645506006361 is an apocalyptic number.

It is an amenable number.

645506006361 is a deficient number, since it is larger than the sum of its proper divisors (215787677799).

645506006361 is a wasteful number, since it uses less digits than its factorization.

645506006361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27336.

The product of its (nonzero) digits is 388800, while the sum is 42.

The spelling of 645506006361 in words is "six hundred forty-five billion, five hundred six million, six thousand, three hundred sixty-one".