643139841600 has 567 divisors, whose sum is σ = 2357445942579. Its totient is φ = 166294425600.

The previous prime is 643139841467. The next prime is 643139841601. The reversal of 643139841600 is 6148931346.

The square root of 643139841600 is 801960.

It is a perfect power (a square), and thus also a powerful number.

643139841600 is a `hidden beast` number, since 6 + 4 + 3 + 1 + 39 + 8 + 4 + 1 + 600 = 666.

643139841600 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 270707927616 + 372431913984 = 520296^2 + 610272^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (643139841601) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 3945643119 + ... + 3945643281.

Almost surely, 2^643139841600 is an apocalyptic number.

643139841600 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

643139841600 is the 801960-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 643139841600

643139841600 is an abundant number, since it is smaller than the sum of its proper divisors (1714306100979).

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

643139841600 is a wasteful number, since it uses less digits than its factorization.

643139841600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 436 (or 214 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 45.

The spelling of 643139841600 in words is "six hundred forty-three billion, one hundred thirty-nine million, eight hundred forty-one thousand, six hundred".