645465563 has 2 divisors, whose sum is σ = 645465564. Its totient is φ = 645465562.

The previous prime is 645465553. The next prime is 645465581. The reversal of 645465563 is 365564546.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 645465563 - 2²⁰ = 644416987 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (645465553) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322732781 + 322732782.

It is an arithmetic number, because the mean of its divisors is an integer number (322732782).

Almost surely, 2^645465563 is an apocalyptic number.

645465563 is a deficient number, since it is larger than the sum of its proper divisors (1).

645465563 is an equidigital number, since it uses as much as digits as its factorization.

645465563 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1296000, while the sum is 44.

The square root of 645465563 is about 25406.0143076398. The cubic root of 645465563 is about 864.2200920173.

The spelling of 645465563 in words is "six hundred forty-five million, four hundred sixty-five thousand, five hundred sixty-three".