644134634352 has 240 divisors, whose sum is σ = 2031981659136. Its totient is φ = 188711424000.

The previous prime is 644134634279. The next prime is 644134634371. The reversal of 644134634352 is 253436431446.

It is a happy number.

644134634352 is a `hidden beast` number, since 6 + 4 + 4 + 1 + 3 + 4 + 634 + 3 + 5 + 2 = 666.

644134634352 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 644134634298 and 644134634307.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 55137952 + ... + 55149632.

Almost surely, 2^644134634352 is an apocalyptic number.

644134634352 is a gapful number since it is divisible by the number (62) 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 644134634352, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1015990829568).

644134634352 is an abundant number, since it is smaller than the sum of its proper divisors (1387847024784).

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

644134634352 is a wasteful number, since it uses less digits than its factorization.

644134634352 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12860 (or 12851 counting only the distinct ones).

The product of its digits is 2488320, while the sum is 45.

The spelling of 644134634352 in words is "six hundred forty-four billion, one hundred thirty-four million, six hundred thirty-four thousand, three hundred fifty-two".