1581043968 has 288 divisors, whose sum is σ = 5480536320. Its totient is φ = 440156160.

The previous prime is 1581043939. The next prime is 1581043969. The reversal of 1581043968 is 8693401851.

1581043968 is a `hidden beast` number, since 1 + 581 + 0 + 4 + 3 + 9 + 68 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a super-3 number, since 3×1581043968³ (a number of 29 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (1581043969) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 1983346 + ... + 1984142.

It is an arithmetic number, because the mean of its divisors is an integer number (19029640).

Almost surely, 2^1581043968 is an apocalyptic number.

1581043968 is a gapful number since it is divisible by the number (18) 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 1581043968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2740268160).

1581043968 is an abundant number, since it is smaller than the sum of its proper divisors (3899492352).

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

1581043968 is an equidigital number, since it uses as much as digits as its factorization.

1581043968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 870 (or 850 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 45.

The square root of 1581043968 is about 39762.3435929021. The cubic root of 1581043968 is about 1164.9697519577.

The spelling of 1581043968 in words is "one billion, five hundred eighty-one million, forty-three thousand, nine hundred sixty-eight".