643090536 has 128 divisors (see below), whose sum is σ = 2011852800. Its totient is φ = 188568000.

The previous prime is 643090531. The next prime is 643090537. The reversal of 643090536 is 635090346.

643090536 is a `hidden beast` number, since 6 + 4 + 30 + 90 + 536 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 643090536.

It is not an unprimeable number, because it can be changed into a prime (643090531) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 69291 + ... + 78021.

It is an arithmetic number, because the mean of its divisors is an integer number (15717600).

Almost surely, 2^643090536 is an apocalyptic number.

643090536 is a gapful number since it is divisible by the number (66) 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 643090536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1005926400).

643090536 is an abundant number, since it is smaller than the sum of its proper divisors (1368762264).

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

643090536 is a wasteful number, since it uses less digits than its factorization.

643090536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8788 (or 8778 counting only the distinct ones).

The product of its (nonzero) digits is 58320, while the sum is 36.

The square root of 643090536 is about 25359.2297990298. The cubic root of 643090536 is about 863.1588070495.

The spelling of 643090536 in words is "six hundred forty-three million, ninety thousand, five hundred thirty-six".