643487580 has 72 divisors (see below), whose sum is σ = 1962795744. Its totient is φ = 170640000.

The previous prime is 643487567. The next prime is 643487599. The reversal of 643487580 is 85784346.

643487580 is a `hidden beast` number, since 64 + 3 + 4 + 8 + 7 + 580 = 666.

It is a super-2 number, since 2×643487580² = 828152531228512800, which contains 22 as substring.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 22705 + ... + 42455.

It is an arithmetic number, because the mean of its divisors is an integer number (27261052).

Almost surely, 2^643487580 is an apocalyptic number.

643487580 is a gapful number since it is divisible by the number (60) 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 643487580, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (981397872).

643487580 is an abundant number, since it is smaller than the sum of its proper divisors (1319308164).

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

643487580 is a wasteful number, since it uses less digits than its factorization.

643487580 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19947 (or 19942 counting only the distinct ones).

The product of its (nonzero) digits is 645120, while the sum is 45.

The square root of 643487580 is about 25367.0569834185. The cubic root of 643487580 is about 863.3364085432.

The spelling of 643487580 in words is "six hundred forty-three million, four hundred eighty-seven thousand, five hundred eighty".