643558413420 has 288 divisors, whose sum is σ = 2297764385280. Its totient is φ = 144286064640.

The previous prime is 643558413419. The next prime is 643558413457. The reversal of 643558413420 is 24314855346.

643558413420 is a `hidden beast` number, since 6 + 4 + 3 + 558 + 41 + 34 + 20 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 972246 + ... + 1494114.

It is an arithmetic number, because the mean of its divisors is an integer number (7978348560).

Almost surely, 2^643558413420 is an apocalyptic number.

643558413420 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 643558413420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1148882192640).

643558413420 is an abundant number, since it is smaller than the sum of its proper divisors (1654205971860).

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

643558413420 is a wasteful number, since it uses less digits than its factorization.

643558413420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 521945 (or 521940 counting only the distinct ones).

The product of its (nonzero) digits is 1382400, while the sum is 45.

The spelling of 643558413420 in words is "six hundred forty-three billion, five hundred fifty-eight million, four hundred thirteen thousand, four hundred twenty".