644042534305446 has 16 divisors (see below), whose sum is σ = 1431205631790000. Its totient is φ = 214680844768464.

The previous prime is 644042534305439. The next prime is 644042534305447. The reversal of 644042534305446 is 644503435240446.

644042534305446 is a `hidden beast` number, since 6 + 4 + 4 + 0 + 4 + 2 + 53 + 43 + 0 + 544 + 6 = 666.

644042534305446 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-3 number, since 3×644042534305446³ (a number of 45 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54), and also a Moran number because the ratio is a prime number: 11926713598249 = 644042534305446 / (6 + 4 + 4 + 0 + 4 + 2 + 5 + 3 + 4 + 3 + 0 + 5 + 4 + 4 + 6).

It is a junction number, because it is equal to n+sod(n) for n = 644042534305392 and 644042534305401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644042534305447) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5963356799071 + ... + 5963356799178.

It is an arithmetic number, because the mean of its divisors is an integer number (89450351986875).

Almost surely, 2^{644042534305446} is an apocalyptic number.

644042534305446 is an abundant number, since it is smaller than the sum of its proper divisors (787163097484554).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

644042534305446 is a wasteful number, since it uses less digits than its factorization.

644042534305446 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11926713598260 (or 11926713598254 counting only the distinct ones).

The product of its (nonzero) digits is 66355200, while the sum is 54.

The spelling of 644042534305446 in words is "six hundred forty-four trillion, forty-two billion, five hundred thirty-four million, three hundred five thousand, four hundred forty-six".