8441721640 has 32 divisors (see below), whose sum is σ = 20720590560. Its totient is φ = 3069716800.

The previous prime is 8441721599. The next prime is 8441721647. The reversal of 8441721640 is 461271448.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 8441721640.

It is not an unprimeable number, because it can be changed into a prime (8441721647) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9592426 + ... + 9593305.

It is an arithmetic number, because the mean of its divisors is an integer number (647518455).

Almost surely, 2^8441721640 is an apocalyptic number.

It is an amenable number.

8441721640 is an abundant number, since it is smaller than the sum of its proper divisors (12278868920).

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

8441721640 is a wasteful number, since it uses less digits than its factorization.

8441721640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19185753 (or 19185749 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 37.

The square root of 8441721640 is about 91878.8421781642. The cubic root of 8441721640 is about 2036.1526904707.

The spelling of 8441721640 in words is "eight billion, four hundred forty-one million, seven hundred twenty-one thousand, six hundred forty".