644511550304443 has 2 divisors, whose sum is σ = 644511550304444. Its totient is φ = 644511550304442.

The previous prime is 644511550304411. The next prime is 644511550304527. The reversal of 644511550304443 is 344403055115446.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 644511550304443 - 2⁵ = 644511550304411 is a prime.

It is not a weakly prime, because it can be changed into another prime (644511550304243) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322255775152221 + 322255775152222.

It is an arithmetic number, because the mean of its divisors is an integer number (322255775152222).

Almost surely, 2^{644511550304443} is an apocalyptic number.

644511550304443 is a deficient number, since it is larger than the sum of its proper divisors (1).

644511550304443 is an equidigital number, since it uses as much as digits as its factorization.

644511550304443 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6912000, while the sum is 49.

The spelling of 644511550304443 in words is "six hundred forty-four trillion, five hundred eleven billion, five hundred fifty million, three hundred four thousand, four hundred forty-three".