581066640 has 480 divisors, whose sum is σ = 2495840256. Its totient is φ = 117642240.

The previous prime is 581066623. The next prime is 581066699. The reversal of 581066640 is 46660185.

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

It is a junction number, because it is equal to n+sod(n) for n = 581066595 and 581066604.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2605569 + ... + 2605791.

Almost surely, 2^581066640 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 581066640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1247920128).

581066640 is an abundant number, since it is smaller than the sum of its proper divisors (1914773616).

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

581066640 is a wasteful number, since it uses less digits than its factorization.

581066640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 307 (or 298 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 581066640 is about 24105.3238932813. The cubic root of 581066640 is about 834.4660025306.

It can be divided in two parts, 58106 and 6640, that added together give a palindrome (64746).

The spelling of 581066640 in words is "five hundred eighty-one million, sixty-six thousand, six hundred forty".