645387550427 has 2 divisors, whose sum is σ = 645387550428. Its totient is φ = 645387550426.

The previous prime is 645387550403. The next prime is 645387550433. The reversal of 645387550427 is 724055783546.

645387550427 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645387550427 is a prime.

It is not a weakly prime, because it can be changed into another prime (645387550727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322693775213 + 322693775214.

It is an arithmetic number, because the mean of its divisors is an integer number (322693775214).

Almost surely, 2^645387550427 is an apocalyptic number.

645387550427 is a deficient number, since it is larger than the sum of its proper divisors (1).

645387550427 is an equidigital number, since it uses as much as digits as its factorization.

645387550427 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 28224000, while the sum is 56.

The spelling of 645387550427 in words is "six hundred forty-five billion, three hundred eighty-seven million, five hundred fifty thousand, four hundred twenty-seven".