645492563 has 2 divisors, whose sum is σ = 645492564. Its totient is φ = 645492562.

The previous prime is 645492541. The next prime is 645492593. The reversal of 645492563 is 365294546.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645492563 is a prime.

It is not a weakly prime, because it can be changed into another prime (645492593) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322746281 + 322746282.

It is an arithmetic number, because the mean of its divisors is an integer number (322746282).

Almost surely, 2^645492563 is an apocalyptic number.

645492563 is a deficient number, since it is larger than the sum of its proper divisors (1).

645492563 is an equidigital number, since it uses as much as digits as its factorization.

645492563 is an evil number, because the sum of its binary digits is even.

The product of its digits is 777600, while the sum is 44.

The square root of 645492563 is about 25406.5456723263. The cubic root of 645492563 is about 864.2321420364.

The spelling of 645492563 in words is "six hundred forty-five million, four hundred ninety-two thousand, five hundred sixty-three".