644111424 has 168 divisors, whose sum is σ = 2026846848. Its totient is φ = 193950720.

The previous prime is 644111407. The next prime is 644111443. The reversal of 644111424 is 424111446.

644111424 is a `hidden beast` number, since 644 + 1 + 1 + 14 + 2 + 4 = 666.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1754889 + ... + 1755255.

Almost surely, 2^644111424 is an apocalyptic number.

644111424 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 644111424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1013423424).

644111424 is an abundant number, since it is smaller than the sum of its proper divisors (1382735424).

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

644111424 is a wasteful number, since it uses less digits than its factorization.

644111424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 673 (or 660 counting only the distinct ones).

The product of its digits is 3072, while the sum is 27.

The square root of 644111424 is about 25379.3503462953. The cubic root of 644111424 is about 863.6153122860.

The spelling of 644111424 in words is "six hundred forty-four million, one hundred eleven thousand, four hundred twenty-four".