646220563 has 2 divisors, whose sum is σ = 646220564. Its totient is φ = 646220562.

The previous prime is 646220537. The next prime is 646220611. The reversal of 646220563 is 365022646.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-646220563 is a prime.

It is not a weakly prime, because it can be changed into another prime (646220363) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323110281 + 323110282.

It is an arithmetic number, because the mean of its divisors is an integer number (323110282).

Almost surely, 2^646220563 is an apocalyptic number.

646220563 is a deficient number, since it is larger than the sum of its proper divisors (1).

646220563 is an equidigital number, since it uses as much as digits as its factorization.

646220563 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 51840, while the sum is 34.

The square root of 646220563 is about 25420.8686515626. The cubic root of 646220563 is about 864.5569196592.

The spelling of 646220563 in words is "six hundred forty-six million, two hundred twenty thousand, five hundred sixty-three".