645764527 has 2 divisors, whose sum is σ = 645764528. Its totient is φ = 645764526.

The previous prime is 645764513. The next prime is 645764543. The reversal of 645764527 is 725467546.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 645764527 - 2¹⁵ = 645731759 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (645764557) 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, 322882263 + 322882264.

It is an arithmetic number, because the mean of its divisors is an integer number (322882264).

Almost surely, 2^645764527 is an apocalyptic number.

645764527 is a deficient number, since it is larger than the sum of its proper divisors (1).

645764527 is an equidigital number, since it uses as much as digits as its factorization.

645764527 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1411200, while the sum is 46.

The square root of 645764527 is about 25411.8973514376. The cubic root of 645764527 is about 864.3535000204.

The spelling of 645764527 in words is "six hundred forty-five million, seven hundred sixty-four thousand, five hundred twenty-seven".