644007134421267 has 16 divisors (see below), whose sum is σ = 896120695864320. Its totient is φ = 410620446700992.

The previous prime is 644007134421239. The next prime is 644007134421283. The reversal of 644007134421267 is 762124431700446.

It is not a de Polignac number, because 644007134421267 - 2⁷ = 644007134421139 is a prime.

It is not an unprimeable number, because it can be changed into a prime (644007134421367) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 576363403 + ... + 577479684.

It is an arithmetic number, because the mean of its divisors is an integer number (56007543491520).

Almost surely, 2^{644007134421267} is an apocalyptic number.

644007134421267 is a deficient number, since it is larger than the sum of its proper divisors (252113561443053).

644007134421267 is a wasteful number, since it uses less digits than its factorization.

644007134421267 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1153851202.

The product of its (nonzero) digits is 5419008, while the sum is 51.

The spelling of 644007134421267 in words is "six hundred forty-four trillion, seven billion, one hundred thirty-four million, four hundred twenty-one thousand, two hundred sixty-seven".