644263362446 has 8 divisors (see below), whose sum is σ = 1054249138584. Its totient is φ = 292846982920.

The previous prime is 644263362401. The next prime is 644263362527.

644263362446 is nontrivially palindromic in base 10.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 644263362394 and 644263362403.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14642349125 + ... + 14642349168.

It is an arithmetic number, because the mean of its divisors is an integer number (131781142323).

Almost surely, 2^644263362446 is an apocalyptic number.

644263362446 is a deficient number, since it is larger than the sum of its proper divisors (409985776138).

644263362446 is a wasteful number, since it uses less digits than its factorization.

644263362446 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29284698306.

The product of its digits is 11943936, while the sum is 50.

The spelling of 644263362446 in words is "six hundred forty-four billion, two hundred sixty-three million, three hundred sixty-two thousand, four hundred forty-six".