645867127 has 2 divisors, whose sum is σ = 645867128. Its totient is φ = 645867126.

The previous prime is 645867097. The next prime is 645867143. The reversal of 645867127 is 721768546.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 645867127 - 2⁷ = 645866999 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (645862127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322933563 + 322933564.

It is an arithmetic number, because the mean of its divisors is an integer number (322933564).

Almost surely, 2^645867127 is an apocalyptic number.

645867127 is a deficient number, since it is larger than the sum of its proper divisors (1).

645867127 is an equidigital number, since it uses as much as digits as its factorization.

645867127 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 564480, while the sum is 46.

The square root of 645867127 is about 25413.9160107214. The cubic root of 645867127 is about 864.3992741734.

The spelling of 645867127 in words is "six hundred forty-five million, eight hundred sixty-seven thousand, one hundred twenty-seven".