645234871 has 2 divisors, whose sum is σ = 645234872. Its totient is φ = 645234870.

The previous prime is 645234839. The next prime is 645234901. The reversal of 645234871 is 178432546.

645234871 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 not a de Polignac number, because 645234871 - 2⁵ = 645234839 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (645234071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322617435 + 322617436.

It is an arithmetic number, because the mean of its divisors is an integer number (322617436).

Almost surely, 2^645234871 is an apocalyptic number.

645234871 is a deficient number, since it is larger than the sum of its proper divisors (1).

645234871 is an equidigital number, since it uses as much as digits as its factorization.

645234871 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 161280, while the sum is 40.

The square root of 645234871 is about 25401.4737958253. The cubic root of 645234871 is about 864.1171211647.

The spelling of 645234871 in words is "six hundred forty-five million, two hundred thirty-four thousand, eight hundred seventy-one".