645557562563 has 2 divisors, whose sum is σ = 645557562564. Its totient is φ = 645557562562.

The previous prime is 645557562473. The next prime is 645557562569. The reversal of 645557562563 is 365265755546.

645557562563 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 645557562563 - 2¹² = 645557558467 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (645557562569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322778781281 + 322778781282.

It is an arithmetic number, because the mean of its divisors is an integer number (322778781282).

Almost surely, 2^645557562563 is an apocalyptic number.

645557562563 is a deficient number, since it is larger than the sum of its proper divisors (1).

645557562563 is an equidigital number, since it uses as much as digits as its factorization.

645557562563 is an evil number, because the sum of its binary digits is even.

The product of its digits is 113400000, while the sum is 59.

The spelling of 645557562563 in words is "six hundred forty-five billion, five hundred fifty-seven million, five hundred sixty-two thousand, five hundred sixty-three".