645055247 has 2 divisors, whose sum is σ = 645055248. Its totient is φ = 645055246.

The previous prime is 645055241. The next prime is 645055249. The reversal of 645055247 is 742550546.

645055247 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 645055247 - 2⁶ = 645055183 is a prime.

Together with 645055249, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 645055247.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (645055241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322527623 + 322527624.

It is an arithmetic number, because the mean of its divisors is an integer number (322527624).

Almost surely, 2^645055247 is an apocalyptic number.

645055247 is a deficient number, since it is larger than the sum of its proper divisors (1).

645055247 is an equidigital number, since it uses as much as digits as its factorization.

645055247 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 168000, while the sum is 38.

The square root of 645055247 is about 25397.9378493609. The cubic root of 645055247 is about 864.0369278448.

The spelling of 645055247 in words is "six hundred forty-five million, fifty-five thousand, two hundred forty-seven".