644544445463 has 2 divisors, whose sum is σ = 644544445464. Its totient is φ = 644544445462.

The previous prime is 644544445427. The next prime is 644544445483. The reversal of 644544445463 is 364544445446.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-644544445463 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (644544445483) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322272222731 + 322272222732.

It is an arithmetic number, because the mean of its divisors is an integer number (322272222732).

Almost surely, 2^644544445463 is an apocalyptic number.

644544445463 is a deficient number, since it is larger than the sum of its proper divisors (1).

644544445463 is an equidigital number, since it uses as much as digits as its factorization.

644544445463 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 44236800, while the sum is 53.

The spelling of 644544445463 in words is "six hundred forty-four billion, five hundred forty-four million, four hundred forty-five thousand, four hundred sixty-three".